First Telescope Buy Guide

Checking a Telescope at a Store

2012-01-20T08:47:00.000-08:00

So you see a telescope at a store and you want to check it out. What do you do?

You can only get the most basic idea of the optics while it's in a store, but you can check it out mechanically pretty well. The mount is actually more important than the optics for most starter scopes. So you can get a pretty good idea of a scope, even in the store.

Mount Stability

Put the scope at different angles then see if it says where you put it. What does it take to make it move off-target? If it moves on its own, it may need balancing. Or it may be junk. If it moves when touched lightly, the same is true. If the mount seems like it might be stable, see if you can balance the scope. This will also tell you if the scope is built to be balanced against the effects of eyepieces or accessories of different weights.

Once balanced, it should be possible to get the scope to stay wherever you put it. If there are locking mechanisms that hold it in place, do they cause the telescope to move visibly when you engage them? If so, that's not good.

How does the scope react to being tapped? Does it stay on target? It should. How about light pressure? Stronger pressure? A thump, like an accidental bump with the arm?

Pretend to swap out eyepieces. Does it stay put as you remove and reinsert the eyepiece? You'll be doing this a lot. You find something at low powers, then swap in a higher power eyepiece. If the scope doesn't stay on target, you'll be frustrated whenever you try to increase magnification, since higher power eyepieces see a smaller area of the sky than lower powers. Which makes finding your subject more difficult if you have to do it with the high power eyepiece all over again.

Focuser Stability

When you adjust focus, does the eyepiece wobble at all or does it travel smoothly along its axis? Once its in a place, can it be jiggled--either in and out or side to side? If so, these are all signs of a poorly made focuser. Are the materials it's made of solid or a bit flexible? They should be rock solid.

Does it hold eyepieces securely, or loosely? You want secure.

Adjustability

If the scope's height is adjustable, can it be moved securely, and does it stay put? Some mounts are only supposed to be adjusted when the scope isn't on them. That's fine. But once it's in place does it stay put? Do any of the stand adjustments present a safety risk to the user? Does the mount allow the telescope to be put on safely? I've known people with high-end name brand telescopes who risk their scope every time they set it up or take it down. Eventually the dice roll against them, and the telescope gets dropped and broken. You may not be in a position to set up or take down the scope in the store, but you can ask. Or have them demonstrate it.

Look for places where you can't be sure of whether something is properly in place or not, or where you're not sure if something is engaged until you let go and see if it starts to fall. You don't want that.

Finder Scope

You should be able to use the finder at any angle from horizontal to straight up without undue strain. You should certainly be able to look through it without bumping your head into the telescope. It should be secure as well. and the adjustments to align it with the main telescope should be easy to use. It won't be any use if you can't line it up easily.

Overall construction

Overall, the scope and mount should use solid quality material. It should feel and function like a precision piece of machinery. Tubes made of plastic or heavy paper-type materials are OK, but they should not be at all floppy--they must support themselves and the optical components accurately and firmly. Any sag or wobbliness are trouble.

The scope should be soundly seated on or secured to the mount.

The mount should be stable and firm.

The optics should adjust smoothly, stay put when they're put in place (the eyepiece or focuser shouldn't creep or wobble).

Also, the scope shouldn't have parts that interfere with its proper use for the sake of cosmetic appearance. Like bulgy plastic dew shields or molded plastic part covers.

Learn to Use Your New Telescope!

2012-01-07T16:21:00.000-08:00

Did you get a new telescope recently? This is the time when the most new telescope owners are made!

Using a telescope isn't entirely natural and easy, no matter what scope you have. In fact, the scopes with the most "ease of use" features are often the hardest to get started with.

A local astronomy club is a good way to find others who can help you learn more about how the get the most out of your telescope. They're using their own telescopes, they will know some good places to use them, vital accessories for them (very few telescopes are sold with everything they really need to be useful), and have tips. The club may have formal classes, or just give you the chance to meet up with others with like interests to yours, and more experience.

There's information available online, but having someone who can actually be there with you and your scope, even if just for a short observing session or daytime practice session, can be invaluable. They can see things in a moment that you won't know to mention online. They can tell you things just as quickly that would make for long murky postings online. The "personal touch" makes all the difference.

Also, don't beat yourself up while you're learning. Learning to see things through a telescope is something you have to do. It's not natural like looking with your eyes without an instrument. If you're experienced with using other optical instruments like binoculars or microscopes it'll help, but a telescope is still a different animal that takes getting used to.

Don't set yourself up for failure by expecting to see observatory photograph views of difficult objects. The Horsehead Nebula doesn't look like the pictures to eye, and it's very, very hard to see even with the correct telescope and accessories. Start by looking at things chosen from a naked-eye astronomy book or binocular astronomy book. Train yourself to find the objects, keep your scope on them, and see the detail in them.

Each scope behaves differently, and you will want to get experience seeing what your scope shows. It's a matter of experience, and you'll find there are several different levels you can achieve as your skills develop. Regular repetition with the right equipment is the key to developing. Each new level brings a new level of enjoyment. Things that didn't look like much before suddenly become far more interesting, even if the equipment hasn't changed at all. You learn to see an notice things that weren't apparent before.

Plus you'll need to learn to be patient and give your eye the time to see what you're looking at. Most beginners spend far too little time actually looking through the eyepiece and relaxing once they've got something to see in it. Your relaxed eye will see far more than an eye that is rushed through a quick "there it is!" look.

Keep your scope stored in a state and location where you can easily use it. Its size and type matter far less in its performance than whether it is simply taken out an used regularly.

If you seem to be hitting a wall, there may be something that needs to change with the equipment, or that you need to know about how to use it. Don't be discouraged, find an answer. Astronomy is not supposed to be difficult. If you find that it is, suspect that there's something else you could be doing other than what you are doing.

Don't be daunted by the fact that there are things to learn. The process of learning them is (or should be) a pleasure in itself. There are many ways to approach doing astronomy, none of the good ways require an overabundance of patience or muleheadedness or a giant egg-shaped head. All they take is normality, an interest, and the ability to ask questions and occasionally follow directions.

Good Time for Bargains, But Watch Out!

2012-01-01T12:32:00.001-08:00

This is a good time to find bargains on telescopes. There are many used scopes for sale as folks seek to clear room for new acquisitions in their homes, or raise money to pay the holiday bills. Stores also receive many returns that are re-sold at low prices. Plus they may have overstock that they are looking to clear out.

One thing to watch out for, though, is the ever-present junk scopes, especially if it's a telescope being purchased for a youngster. These aren't bargains at any price. Find yourself a scope with a good price, but first and foremost, remember that it's a scope that should be quality.

A good mount is critical. Half your budget or more should go to ensuring that you can point your scope at what you want to see, and keep it on while you observe.

Many wishes for a happy new year of telescope use!

Observing with a 60mm Telescope: Technical Details

2011-11-19T03:32:00.000-08:00

When determining what you can do with any telescope, there are some equations which give you an idea of what you can expect from your telescope. These equations are estimates, as they don't take into account the construction details of your particular scope. The better your scope is optically, the closer it will come to these estimates.

But in any case, real, practical observing and the skill of the observer will be more important than numbers turned out of an equation. So all these numbers should be taken with a shaker-full of salt. Like the gas efficiency numbers for a car, they're a basis for comparison but not reality.

Lowest Useful Magnification

The equation for this is the diameter of the telescope divided by the observer's pupil size when open to its widest. Basically it measures how large the image can get before light is lost outside the observer's pupil:

Lowest Useful Magnification = D / p

Where D is the telescope's objective diameter, and p is the pupil diameter. The rule of thumb version is:

D(in inches) x 4 for a 6mm pupil (older adult average pupil)
D(in inches) x 3.6 for a 7mm pupil (younger adult average pupil)
or
D(in mm) / 6 for a 6mm pupil,
D(in mm) / 7 for a 7mm pupil.

With a 60mm telescope, that gives us a minimum useful magnification figure of 9 or 10 powers.

This is tempered by the practicality of getting an eyepiece that's one ninth or one tenth of the focal length of your telescope's objective. If you have a 60mm f/10 telescope that would be about a 60mm focal length eyepiece! Typically the longest eyepiece focal lengths you'll find in a size for your 60mm telescope are about 45mm. This would give the 60mm f/10 a magnification of 13.

A 60mm f/6 telescope has a focal length six times 60mm, or 360mm. A 36mm eyepiece would give 10 power in this telescope. A 42mm eyepiece would give a magnification just under 9 powers.

What does this mean?
What this means is that it's just about impossible to go to powers that are too low for your 60mm telescope to be useful. As a matter of practice, it's not really a problem to go below the "lowest useful magnification" by a bit, as in the example of the 60mm f/6 with a 42mm eyepiece. You'll lose a little light outside the area of your pupil, but the eyepiece will also be a bit more forgiving about how you position your eye next to it. It also adds to the "spacewalk" experience when your eye can get image even when you move around a bit at the telescope.

Low powers are also where you'll typically get the widest field of view from your telescope. They are well suited for looking at dim deep sky objects, concentrating their light into a smaller area in your field of view, making them easier to see in spite of your limited light gathering power.

Minimum Magnification to See Finest Detail
This is a calculation to estimate what magnification you should use to make out the finest detail in well-illuminated objects like planets and the Moon. If you are below this magnification, you're missing some detail, theoretically. If you're above this, the light on dim, marginal objects will be spread out, possibly causing some detail to be lost.

In practice, this is a decent estimate of the highest magnification for the scope for general use, and the highest usable magnification for the scope will be about twice as high with brighter objects.

The calculations assume that the observer can see detail down to about 100 arcseconds without a telescope.

A simple way to calculate it is 100/R, where R is the resolving power of the telescope in arcseconds. For a 60mm scope, R is about 3.0 in practice, as low as about 1.9 in theory. This gives us values from 33 powers to 52 powers.

This result again emphasizes that the 60mm scope is at its best at low powers of magnification. It gives us a practical top magnification for image details at around 70 to 100 powers depending on how good conditions are. Better conditions allow higher powers. The lower powers are the magnification that will give the finest detail on planets, the Moon, in nebulas, and so on. The higher powers are how high you can normally expect to go without losing lots of internal detail. In objects where internal detail is not as important, such as a galaxy where you're trying to find the outer extremities, you can go to lower power to raise surface brightness. Along the Moon's terminator, where contrast is very strong, you can probably still see plenty of detail at higher powers.

Maximum Useful Magnification
This is another useful rule of thumb. It's also based on the aperture of the scope. This is one of the things that causes "aperture fever", where amateur astronomers keep going for larger and larger telescopes. In fact, the contrast of the image will determine what can be seen with the scope and how well it will work with higher levels of magnification as much or more than the aperture. But contrast is tricky to measure, while all it takes to measure aperture is a ruler and the open end of a telescope.

Standard rules of thumb for this figure are as follows:
M = 20 x D(inches) or
M = 0.8 x D (mm)

For a 60mm telescope, this gives us a maximum magnification of about 48 powers. The rule of thumb also states that typical magnification should be about half this value to get maximum brightness and contrast.

Does that mean your scope is useless at powers higher than about 50? No way! This is a rule of thumb more applicable to larger scopes (6 to 30 inches) than it is to smaller scopes. Also, this number will vary dramatically depending on the optical quality of your scope. The highest quality refractors in 60mm aperture can give great detail at over 300 powers under the best conditions. But this isn't too bad a measure for a scope of moderate performance. Basically, while the number it produces is low, it again emphasizes that the best performance for a small scope is at relatively low powers. You'll see more if you use your scope in the way that it works the best.

Theoretical Limiting Magnitude
This is the theoretical dimmest star you can see with your telescope. For your 60mm this is a magnitude of 10.6. The highest quality scopes will outperform this, and poorer scopes won't do this well. My experience is that the contrast of the image the scope gives, and the quality of the sky--how dark the background of the sky is--have the strongest effect on this.

For "extended objects", that is, anything that doesn't have all its light in a single point like a star, the apparent magnitude is a measure of all its light put together. So if you find a galaxy in a catalog that has a magnitude of 10.4, it may well not be visible in your 60mm telescope, even though your scope can theoretically see even dimmer objects. The problem is that the light is spread out over a larger area, so that the light at any point is too dim for the telescope to show it.

Putting It All Together
Upshot for a 60mm telescope, keep your powers low to see the most. Pick bright objects to observe. Get to dark skies if you can. Get the best optics possible, and remember that optical quality doesn't matter at all if you're not working on a good, solid mount that holds the scope on target.

Observing Galaxies with a 60mm Telescope

2011-11-12T02:49:00.000-08:00

This article is part of a series I'm doing on observing with 60mm telescopes. 60mm telescopes are among the most common of first telescopes. My own first telescope was a 60mm which I used for over 10 years, before "moving up" to a 75mm, then over 20 years later to a 200mm telescope. The points in this article are applicable to larger scopes than 60mm, though it is written about 60mm scopes.

In the first article in this series I listed a number of galaxies that can be seen with a 60mm scope. Here I'll cover some of the best, along with tips on how best to observe them with a small telescope.

Conditions for Observing
With a small scope, small things can make a difference between success and failure when observing faint objects. The sky must be right. Low atmospheric moisture levels mean better contrast and more light from the galaxies you want to view. The telescope must be right. It should be in good condition, with clean optics, and most importantly of all, a stable mount that holds the telescope securely on its target, and allows the scope to be moved and pointed easily. The observer should be in a relaxed, unhurried mood.

Bright Galaxies
There are a few galaxies that are bright enough to be seen easily, even with a 60mm telescope. The Andromeda Galaxy, M31, is one of these. In the southern hemisphere the Large and Small Magellanic Clouds are visible to the eye, so they're easy to find and point the scope at. They're also bright enough to show a lot of detail. M31 is too large to fit into the field of view of a normal telescope, but the brightest parts of the halo, the disk part of a spiral galaxy, and the nucleus, the ball of stars at the center of a spiral galaxy, are visible. It is a good observing exercise to see how far from the nucleus of M31 you can go while still being able to tell the halo of M31 from the background sky.

Low powers will give the best contrast in a small telescope like a 60mm. It is more important to be able to make out the galaxy against the background to see it than it is to magnify the detail in them. The higher the level of magnification, the more the light from the galaxy gets spread out, lowering the contrast. The brightest galaxies, like M31, LMC and SMC, M65 and M66 will allow some moderate magnification. Still, they are best viewed at the lowest power possible with the telescope.

If you don't have an eyepiece with a longer focal length than 25mm, you may consider getting one just for observing deep sky objects at low powers with your telescope. either 32mm or 40mm are fairly common. My 40mm eyepiece is my favorite for viewing galaxies, and once it goes into the focuser for the evening, it almost never comes back out.

Dimmer Galaxies
There are many dimmer galaxies visible with a 60mm telescope. Don't expect them to look like the photographs. They'll look like fuzzy gray spots. But they'll have different shapes, brightnesses, and distributions of light across their visible form. Some will have bright centers and dimmer areas around, others will be equally bright all across, others yet will be splotchy or broken into multiple sections.

Near M31 there are two other galaxies, M32 and M110. They are much, much smaller companions of M31, like the LMC and SMC are companions of our galaxy. They are easy to see because they have a high surface brightness. This is the most important determinant for whether a galaxy will be visible in a small scope.

The apparent magnitude is the brightness listed in sky catalogs for galaxies. It's a misleading number, because it is the measure of how much light it would put out if all its light were gathered into one point of light, like a star. But the light is spread out over the whole face of the galaxy.

How much light is put out by any specific part of the galaxy you see is the surface brightness. A galaxy may be bright, but have a low surface brightness. The Triangulum Galaxy, M33, is like this. It is visible in a 60mm scope, but only with difficulty, because any part of it is very dim. Its total light is spread out over a large area of sky. M110 is very bright at any point. It is compact and well defined, making it easy to see compared to M33. So when reading descriptions of galaxies, look for those with a high surface brightness to view with the 60mm scope.

M108 and M109 in the Big Bear both have a high surface brightness. They are spiral galaxies that we see edge-on, so they appear as a short line of light or small lens shape near different parts of the Big Dipper.

M65 and M66 are bright galaxies in the leg of Leo, The Lion, that can be seen together in the same low power field of view. So you can see, and show others, two galaxies at once! There is a third galaxy nearby that's a bit dimmer, but if you can see it, you'll have three galaxies at once.

Observing the Deep Sky with a 60mm Telescope

2011-11-06T01:18:00.001-07:00

"Deep Sky" observing is not normally associated with a telescope as small as a 60mm (2.4 inch). There are many nice objects that can be viewed well with a small telescope, however. This is part of a series of articles on this blog about observing with the 60mm telescope. The information also applies to larger scopes, which can get even more out of these objects with their greater observing power.

There are a good number of objects that most any 60mm scope can show well, so long as they have a decent mount. The Lagoon and Trifid Nebulas, the Hercules Cluster, the Great Orion Nebula, the Crab Nebula, and many star clusters are all wonderful objects to show off the abilities of your small scope.

60mm scopes with the highest quality optics and very good mounts can show objects that are usually thought of as objects requiring larger telescopes. Better mounts give a steadier view, and allow you to relax more while looking. Better optics improve the contrast of the image, which makes it easier to find and see the object you're looking for, and to see more of the detail in it.

Star Clusters
Star clusters are the deep sky objects your small scope is most suited for. They are relatively bright, and very numerous, meaning there'll almost always be plenty of them in the sky to choose from. There are two basic types of star cluster, the "open" cluster, which is a general group of stars that happen to be near each other, and the "globular" cluster, which is a group of stars whose mutual gravity has pulled them together into a globe shape.

Both types are visible in your 60mm telesccope. In my first article in this series I listed a good selection of star clusters that can be viewed with a 60mm scope. Here's I'll describe some of my favorites, and observation tips that apply to all clusters.

Globular Clusters
M13, the Great Hercules Cluster, is a showpiece object for northern hemisphere astronomers. It's a big glowing ball of stars in the Keystone of Hercules. Different globular clusters look different. Some have a very even brightness across the face of them, others are brighter at the center then the brightness tapers off as you go outward. M13 is one of these, much brighter at the center. Its brightness drops off regularly from center to edge. Individual stars can be picked out at the edges, with tendril-like streams of stars flowing outward around M13s boundaries.

Compare this with M22, near the top of the Teapot in The Archer, visible to observers north and south. It is about the same brightness as M13 overall, but the bright wash of its center extends well across its diameter. Only the outer parts dim. Southern observers can also enjoy the enormous globular Omega Centauri. M13 and M22 are both visible to the naked eye, but not like Omega Centauri! In the telescope, Omega Centauri shows enough detail to spend a lot of time enjoying it.

Open Clusters
Star Clusters with no particular form are also beautiful in a 60mm. A good night with high contrast skies will show these the best, making more stars visible in the cluster as well as making them stand out clearly from the background sky.

The Beehive Cluster and Alpha Persei Moving Group are beautiful groups of bright yellow stars. As is the case for star clusters in general, they should be viewed at the lowest power you've got for your scope. This would be the eyepiece with the longest focal length. This is the number shown on the eyepiece, usually given in millimeters (mm). Sometimes a viewing angle or other number is listed as well, but the focal length is usually listed most prominently in this case. The one with the largest number gives the lowest power views. For example, a 25mm eyepiece will give lower power magnification than a 15mm eyepiece.

The Seven Sister, or Pleiades (M45) are spread out too far to be seen all at once in nearly all telescopes. But the area can be scanned at low power. About 40-some stars are visible in all under the best conditions, and faint nebulosity (cloudiness) is visible in this area as well.

M39 is a nice, tight cluster at the edge of the area of sky that holds The Swan. It is easily contained in the telescope's field of view, and stands out nicely from its background.

Nebulas
Nebulas are clouds of gas and dust. There are several different sorts. Planetary nebulas are ones that tend toward being round, looking a little like "planets", which is why they have that name. They have nothing to do with planets other than looking a little like the disk that a planet shows. Supernova remnants are clouds of material that have been blown into space by an exploding star. Most commonly seen nebulas are general clouds of gas and dust in the spiral arms of our galaxy. Many of these are places where new stars are being formed, so they are often associated with nearby star clusters.

There are a few bright star clusters that look really good in a 60mm telescope. Most, however, are faint, show little detail, and are very hard to see in a small scope. The Great Orion Nebula near the belt of Orion, and the Lagoon and Trifid Nebulas in The Archer are among the best. On a clear night with a dark sky they show up clearly, with traceries of their gas and dust forming streamers and shapes inside and around them. At their best, they can show a faint greenish color, though they'll usually just show shades of gray in a 60mm.

The Crab Nebula, M1, in Taurus, is a fine supernova remnant for small telescopes. It is relatively easy to find, near the tip of one of The Bull's horns.

Fainter nebulas can be seen as small cloudy shapes. They are a good way to develop your skill as an observer, both in finding them and in observing their form. NGC 6334 lies near the star cluster M6, and is a good starting point for seeking more challenging nebulas.

Many planetaries are very nice to observe in a 60mm scope. Their compact form and well defined edges make them easier to see than a lot of the more "gaseous" looking nebulas.

The Saturn Nebula, NGC 7009, in Aquarius the Water Bearer, is very bright and has a nice green color visible even in small scopes when the sky is good. The Eskimo Nebula, NGC 2392, in Gemini the Twins, is fainter, but its form can be made out easily once found. The Ring Nebula, M57, in Lyra is a favorite of small scope owners. It looks like a smoke ring. It is bright enough to take your scope to its highest magnification, as is the Saturn Nebula.

In the next article I'll cover the final sort of deep sky object you can see with a 60mm: galaxies.

Observing the Moon with a 60mm Telescope

2011-10-30T01:07:00.000-07:00

This article is part of a series on using and observing with a 60mm telescope, one of the most common of beginner telescopes. The information also applies to larger scopes, which can show more detail and find objects that are difficult with a 60mm scope more easily.

The 60mm scope can be a very rewarding scope to use, however, especially when getting started. They are compact, often inexpensive, even for quality scopes, and easy to use when well designed. They remain useful even when there are better scopes in the house because of their small size, light weight, and general ease of use.

I used a 60mm scope as my primary telescope for over 10 years. My first scope was a 60mm telescope, unfortunately mated to an extremely poor mount. I fought the mount for many years, if I had been less mule-headed I would have probably given up on astronomy. Fortunately, I finally decided to rebuild my mount using wood from my school's wood shop scrap bin. It looked awful, but held the scope on target and steady. The optics were actually pretty good, once they stayed where they were put.

Observing The Moon
A 60mm is enough scope to enjoy practically everything the Moon has to offer. The craters, valleys, walls, ridges and seas of the Moon will all stand out nicely at low to medium powers (25 to 150 powers). If your telescope has a clock or computer drive you will also be able to use higher powers on the Moon (150 to 250 powers). It is one of the few objects that is bright enough for high powers for a small telescope. But it will be a lot harder to get a sharp focus and to stay on your target at higher powers.

The best place to look on the Moon's surface for nice detail is near the dividing line between night and day on the Moon. This is where the contrast is the sharpest. Plus, you can see changes as time passes in these places. One of my favorite things to do is find a crater where the rim is in sun, but the floor is still in darkness. Sometimes, every so often, I can watch the Sun illuminate the central peak of a crater as I watch. It'll go from darkness to a sudden spot of light in the middle of the crater. Other times I'll look at an area, go look at other things elsewhere, then come back an hour or so to see if anything has changed in areas I've looked at earlier in the night.

Many parts of the Moon will be too bright to show much detail, or will be so bright in the telescope that it'll ruin your night vision. In this case the little Moon filters that come with many telescopes, designed to be fitted to the eyepiece, can be helpful in cutting the light down to a more tolerable level and help bring out some contrast. Unlike the little solar filters, these are safe to use. If a Moon filter didn't come with your telescope, there are many color and "neutral density" filters available that you can get inexpensively.

Neutral density filters are strictly "black and white" filters that cut down brightness without changing the colors of what you're looking at. They are my favorite for using on the Moon, especially when I'm looking for color on the Moon. One sort is a polarizing filter, which can be adjusted to different darkness levels. These are also useful for seeing cloud details on Venus, but they tend to be expensive.

Color filters also work well on the Moon. Darker colors often come in packs of different color filters that are commonly sold. About the only object these darker filters are useful on is the Moon. Dark red, orange, green, and yellow filters will each have a different effect.

Light color filters are nice for bringing out detail in areas of the Moon where there is some color in the soil. These colors are very faint, and the filter will eliminate the ability to see the colors directly, but they will bring out more detail of the surface in these areas.

Be careful of trying to take the magnification too high. It's tempting on the Moon, but more detail will actually be seen at moderate powers by relaxing (a couple of deep breaths are always good) and taking the time to let the subtle details of the image "sink in" as you view.

Observing the Sun and Planets with a 60mm Telescope

2011-10-23T05:17:00.000-07:00

In What Can I See With a 60mm Telescope I gave brief lists of some of what you can observe with a 60mm telescope, with just the briefest of notes on hoow to do that observing. Now I'll cover some of the details of how best to observe the objects mentioned in this and subsequent articles.

First, the Sun and the planets. The Moon and the various deep sky objects are large enough subjects that I'll cover them by themselves elsewhere.

Magnification

You can use both medium and low magnification on the planets when observing them. They are bright enough that even with a 60mm telescope you can enlarge the image with magnification and still see some detail where there's detail to be seen. Each planet observable with a 60mm scope is detailed below.

For a 60mm scope, low magnifications range from about 20 powers (or 20 diameters, if you prefer), to about 100 powers. Medium levels of magnification are the highest practical magnification levels for this size scope. A 60mm will not allow what is typically referred to as "high" power magnification. Medium powers run from about 100 powers to about 200 powers. Anything more in this size scope will result in such a loss of detail and contrast that you'd actually see more at lower powers.

If your scope has eyepieces that claim to give higher levels of magnification, take them out of your usual kit of stuff you take observing with you and set them aside for another telescope. You'll get the best views from your 60mm at magnifications from 40 to 120 powers, the scope is usable up to 150 powers or so, and can be used at up t0 200 powers if everything about the scope and the sky is perfect. Higher levels of magnification are theoretically possible, but are, in practice, show far less than lower powers.

Mount
In this size range of telescope, the mount is actually far more important than the optics of your scope. Most optics in this range are pretty good. The finest optics and best designed 60mm telescope will show far more, of course! But to show anything the mount must be able to hold the scope steady and on the object you've pointed it at.

Plus, to observe using higher powers (over about 120-150x), the mount will have to have either good slow motion controls or a clock or computer drive. Mounts without these will work perfectly well at the lower powers, my mount for my 60mm has no drive or slow motion controls.

First and foremost, though, the mount has to hold the scope still. It shouldn't slide down or up when locked in place. It shouldn't shift halfway across the sky when the position is locked in. It should be possible to thump the scope lightly and not have it move off target.

There are many 60mm telescopes sold with good mounts today. There are also very, very many sold with the awful mounts of yesteryear that frustrated the heck out of me. The best thing I ever did with my 60mm scope was build a new mount that actually held it in place. You can do even better, by getting a good mount that works well right from the start. If you can get one with either a drive mechanism or with slow motion controls, that's nice. If not, don't fret. You can do a lot of observation with even the simplest stable mount.

The Sun
The Sun is only safe to view if you have a solar filter that fits over the front of the telescope. The sort that goes on the eyepiece is not safe to observe with, they will overheat and crack. If somebody's eye is there when that happens, that eye will be blinded forever by the damage from the concentrated sunlight. I have literally had one of these filters crack just as I looked away from the eyepiece. Don't trust the little eyepiece sun filters, not even for a moment. If one came with your scope, throw it away before you are tempted to give it a try.

If you do have a proper filter, your scope will show you the surface of the Sun, including any sunspots visible on it. You can watch the sunspots move as the Sun turns. They are most interesting to watch as they appear and disappear at the edges of the Sun.

Rarely, either Mercury or Venus will pass between the Earth and the Sun. This is called a transit. Usually it can only be seen from a particular part of the Earth that's lined up right. But, if you have a properly outfitted 60mm telescope for solar observation, and you're in the right place at the right time with nothing blocking your view, you can observe a transit with your telescope.

More common is a solar eclipse, where the Moon passes between us and the Sun. A telescope fitted for solar observation can also be used to watch a solar eclipse close-up.

Mercury
Mercury appears as a small orange-red disk in a 60mm telescope. It doesn't show any detail, but its color will change depending on the sky conditions you observe it under. It is always near the Sun, so it can only be observed near sunrise or sunset. Sometimes it can be seen during the daytime, but it is so close to the Sun that it's not really safe to observe without the chance of accidentally moving the telescope onto the Sun.

Venus
Venus appears as a small, bright, Moon-like object. It shows phases, and can be magnified to the limit of your scope's ability. Rarely, cloud detail can be viewed in a 60mm with a variable polarizer filter, though it usually takes a larger telescope to manage this.

The phases of Venus are quite distinct, looking just like phases of the Moon.

Venus can be observed safely in the daytime when it is far away from the Sun, at or near what is called "greatest elongation" which is astronomer-speak for farthest it gets from the Sun. Be very, very careful when locating it, however. Initially align your telescope without your eye at the eyepiece or the finder scope, using the shadows cast by the Sun to make sure that the scope isn't pointing at the Sun. Then, sweep away from the Sun, never toward it. If you need to go back closer to the Sun, take your eye away from the scope or the finder, move the scope while watching the shadows, don't put any body parts in line with the eyepiece (the Sunbeam that comes out of it will burn), better yet, cover the objective of the telescope when going back toward the Sun. Then again sweep away from the Sun.

When seen during the day, Venus looks like a little Moon as seen during the daytime.

Mars
Mars shows some surface detail, unlike Mercury and Venus. It will show light and dark areas at medium power. A polar cap is visible, especially when the position of Mars and its season is right, when the polar cap may cover about 1/4 of the visible planet's disk. Mars has an especially nice display about once every two years, when it is closest to the Earth.

Its two moons are too small to be seen, even in much larger telescopes, so don't expect to find them. If you see something nearby, it's likely a background star, or possibly an asteroid if it appears to move rapidly with respect to Mars (rapidly meaning about as fast as a clock's hand!)

Color filters can bring out subtle detail in Mars' surface when Earth is close enough to make Mars look its largest (it never, never gets as large as the Moon, however! That's just an internet myth.) Light colored filters work the best, I use very light yellow and blue filters, and occasionally a very light orange filter, to bring out details of light and dark areas on the surface of Mars at about 200-250 powers when everything--sky, mount, telescope, my eyes--are at their best.

Ceres and the Bright Asteroids
About a dozen asteroids are visible to a 60mm scope in any given year. Finder charts for them are online and in the major astronomy magazines and their annual supplements. None of them shows the form of a disk, they all appear as stars, at best.

They are most interesting to observe when you can watch them from night to night, seeing the movement of the "star" relative to the other stars near it.

Rarely, there will be an asteroid that is rotating at a rate that makes it brightness change as you watch. These are incredibly interesting to see, as it is so rare, and such a clear sign that that "star" is not like the others.

Jupiter
Jupiter is one of the things that your 60mm scope was built to view. It is a showpiece for your scope. It's what you show visitors so that they can say, "Wow," when they look through your scope.

Jupiter will show bands in its atmosphere, even at low powers. If the Great Red Spot isn't busy blending in with its background, it will be visible at the highest powers your scope can achieve (sometimes it's more visible than others.) It was very obvious back in the 1970s and 1980s, but then it began to dim and fade in with the cloud belt it is in. Now it is becoming somewhat more visible again. Hopefully it will continue to do so. Back in the 1970s it looked like a great big cherry, standing out clearly from its cloud belt even in a 60mm scope.

Larger scopes often have to block off some of the excess light from Jupiter when it is at it brightest. You are unlikely to have that problem with a 60mm. You should be able to see at least two dark bands, one above and one below, as well as the dark areas at each pole easily. That makes seven stripes (four dark, three light) that you should be able to see, even with so-so optics. Fine, high quality optics show far more, including far more detail within each of the bands such as veils, columns, rifts, bays, garlands, tails, festoons, and numerous other features. This is why people pay more for better optics, even in small scopes.

Jupiter's Moons
The four Galilean Moons will be easily visible through the 60mm scope. They will appear as small stars in line with Jupiter's equator. Occasionally, their shadows can be seen on Jupiter's surface, or they can be seen to cross in front of Jupiter if you have good optics. Their movement changes noticeably over the course of an evening, but if you just sit and watch them it's like watching the hour hand move, so memorize where they are, go look at something else, then come back for another look later.

Saturn
Saturn is probably the best object to see in your 60mm telescope. My wife still tells the story of how she "discovered" Saturn in her 60mm telescope when she was young.

The planet is bright, the rings are easy to see at 40x and higher. Careful observation with a relaxed eye will show bands in the atmosphere of the Saturn. The angle of the rings varies over time. When the rings are "open", that is, tilted at a higher angle and not edge-on, the Cassini division is visible in the rings. Better optics will show other divisions and more detail in the rings.

The moon Titan shows easily in all 60mm scopes. It appears as a bright star near Saturn. Four, and possibly as many as six, other moons will be visible. Seeing all seven moons that are possible with the 60mm requires absolutely perfect conditions and the highest quality optics. Normally, Titan will be easy, and two to four other moons will be visible with varying levels of difficulty.

Uranus
Uranus appears as a small disk, often with a faint greenish color to it when it is at its brightest. None of its moons are visible, nor are any details of its surface. Low powers show it the best, and throwing the image slightly out of focus may reveal color when none is visible otherwise.

Neptune
Neptune appears as a very small disk at the higher powers for your scope. When at its brightest, it may show a slight blue color. No detail is visible on the disk. This is a challenging object to observe with a 60mm scope, it is often very hard to tell Neptune from nearby stars. No moons are visible.

What Can I See With a 60mm Telescope?

2011-10-15T15:08:00.000-07:00

60mm telescopes are among the most common and most popular. They are inexpensive, generally, don't take up too much space, and easy to come by. Most of them have optics that range from decent to good, with a few very good models out there. 60mm is enough light gathering power to enjoy a lot of different objects in the sky.

I used a 60mm scope as my main telescope for over 10 years before "moving up" to a 75mm reflector. During that time I learned how to get the most out of my telescope as my abilities advanced and I learned both more about the sky and more about using a telescope. My wife still owns a 60mm telescope, and though our household has many larger scopes, it still comes out to the front yard or back porch on occasion for casual observing sessions. It's light, easy to use, and enough telescope for many objects in the sky.

The thing that holds a lot of these smaller scopes back, especially at the low end of the price range, are poor mounts. But, if you can put your scope on target and get it to stay there, here are some of the sights you can expect to enjoy with your 60mm (2.4 inch) telescope.

In this article I'll be covering a brief list of what you can see with a 60mm telescope, which may be far more than you'd expect for such a modest aperture. There are a few objects that are downright magnificent, even with such a small scope. These are the brighter objects, where the mere 60mm of light collecting power is not a disadvantage. Most objects will have much more subtle detail, however, and will require more patience at the eyepiece to appreciate fully.

There are also objects that the challenge of observing them at all in such a small instrument is part of the fun. Collecting star clusters, globular clusters, or galaxies observed in a 60mm telescope can be a rewarding occupation all on its own. Plus, if you have the opportunity to use a larger telescope, you are already skilled at finding challenging objects, and can see your old friends with far greater detail.

Here are some of the things you can see with a 60mm telescope. Subsequent articles go into more detail about observing each of the different types of objects with your small scope. These objects are also good in larger telescopes that gather more light. They'll usually be easier to locate and will show more detail in larger scopes.

The Moon
Craters, mountains, seas, rifts, valleys, searching for colored areas on the Moon. The 60mm scope turns the Moon from a bright object in the sky into a world whose terrain you can explore.

The Sun
Use only a full-aperture filter over the front of the telescope. Never use one of the little eyepiece solar filters! You can observe sunspots, transits when they occur, and eclipses.

The Planets
Mercury, Venus, Mars, Ceres, Jupiter, the Galilean Moons of Jupiter, Saturn and its rings, Titan and four other moons of Saturn (possibly as many as seven moons total under perfect conditions!), Uranus, Neptune. Jupiter and Saturn are two of the finest showpieces in the sky for the 60mm scope.

Other Solar System Objects
Typically about a dozen asteroids will be bright enough on any given year to be seen with a 60mm telescope. Also, usually two or three comets appear that can be seen, sometimes more.

The Stars
Stars are the forte of the 60mm telescope aside from the Moon, Jupiter, and Saturn. In particular, double and triple stars and the brighter, tighter star clusters. Mizar and Alcor in the Big Dipper make a good start for northern hemisphere observers, then zooming in on Mizar to see both Mizar and its companion, Mizar B. Just to the south of Alcor and Mizar lays double star Cor Caroli in the Hunting Dogs. Leo contains several nice double stars for observers in both hemispheres, and there are many, many more spread throughout the sky.

When observing individual stars and double stars you will be able to take your telescope to its highest practical magnification levels, about 150 to 200 powers if you have a good mount and either a clock drive or good slow motion controls on an equatorial mount. Otherwise, you will still get plenty of good observing at magnifications of about 50-100 powers. More on this is later articles.

Colored Stars
Most stars appear pretty well white. But some have a distinctive color. Herschel's Garnet Star in The Charioteer is a star that shows its color most strongly in small telescopes. In larger scopes the color begins to "wash out". It is a bright red in a small scope, becomes amber in a larger scope, and finally a watery yellow in the largest amateur telescopes. The double star Albireo in The Swan is a pair of stars of differing colors, each one setting off the color of the other, one yellow, one blue. The Red White and Blue triplet in The Swan is another close group where the color of each sets off the colors of the others. There are many nice colored stars in many constellations.

Star Clusters
When observing star clusters you will usually want to view with the lowest possible magnifications for your telescope to see as much of the sky at once as you possibly can. Many 60mm telescopes come with eyepieces that give far too much magnification for the aperture of the scope, but they don't come with eyepieces that allow the scope to work at the incredibly useful low levels of magnification they are capable of. Eyepieces of 35mm and 42mm and thereabouts make great "sky sweeping" eyepieces, and are the sort of thing you want for most "deep sky" objects.

There are many star clusters you can enjoy with the 60mm telescope. Some are too large to see all at once but can be "swept" to be enjoyed. There are two basic types of star cluster. The "open" cluster and the "globular" cluster. The globular cluster looks like a globe of stars. Open clusters vary from ones that look almost exactly like globulars to loose groups of stars that are near each other.

Here are some you can see in your 60mm:
Double Cluster in Perseus, M13 the Great Hercules Cluster, M103, M7, M6, M39, M22 the Arkenstone, M70, M54, NGC 6242, NGC 6281, M80, M4, M2, M5, NGC 6231, M45 The Seven Sisters, M11, M17, M62, M55, M28, M54, M69, M75, M26, NGC 6664, NGC 6712, NGC 6649, and many more. If that sounds like a lot of gobblety-gook, it's because I've mostly just given the "short" name of the cluster, which is a catalog number. Most of these are from the Messier catalog (the M numbers), a great list of objects to observe with a small telescope.

Deep Sky Objects
Star clusters are one type of "deep sky object", which is basically anything that isn't a solar system object or an individual star or star system (in the case of double, triple, and other multiple star systems.) You can see galaxies, nebulas (space clouds) and other things with your 60mm as well.

Galaxies:
M31, M110, M32, M33, M65, M66, M51, M101, M108, M109.

Planetary nebulas are roundish clouds of dust and gas thrown off by some stars:
M27 The Dumbbell Nebula, NGC 40, NGC 246, NGC 1535, NGC 2392 The Eskimo Nebula, NGC 3132, NGC 3242, NGC 6210, NGC 6543, NGC 6572, NGC 6826, NGC 7009 The Saturn Nebula, NGC 7662, M57 The Ring Nebula.

Other nebula don't have any particular type of shape:
North America Nebula, Pelican Nebula, The Great Orion Nebula, M8 The Lagoon Nebula, M20 The Trifid Nebula, Rho Ophiuschi, NGC 6334, and many more, particularly near the Milky Way.

Dark nebulas are dark clouds of gas and dust that are often outlined by bright objects behind them. There is a dark nebulosity about 2 degrees south of M62, Barnard 86 is a dark nebula in The Archer in the Milky Way. There are many others, in Orion and elsewhere, that you can see.

Star clouds are areas of our own galaxy that are especially rich in stars. They are too large to be seen all at once through the scope, but they make impressive areas of the sky to sweep through with the 60mm telescope. M11 The Scutum Star Cloud, in The Shield, is the largest and most impressive but sweeping along the length of the Milky Way at the lowest power possible will turn up many areas where your view will be filled with countless stars.

In future articles I'll give more details and tips on observing these different types of objects with the small telescope. If you've got a larger scope than 60mm, remember, you can see these objects, too, and in more detail.

Your Telescope Can't See It Till You Find It

2011-08-05T09:15:00.000-07:00

Aside from a a stable, well-made, the most important part of your telescope is the finder. You need the mount to hold your scope on what you see, and you need the finder to get it there in the first place. Even a set of so-so optics won't be as damaging to your viewing experience as a problem with either the mount or finder.

Finding the Right Finder

One thing to watch out for in a finder is finders that are made to look good, without actually being good. My favorite finders to hate are the little telescope-looking things on the side of the scope with a cheesy little ring-mount with three screws.

Reflex Sights: Red Dots and Red Rings

For most users, I recommend a Telrad or a similar red-dot/red-ring finder. It doesn't magnify or vignette your view of the sky, so finding things in the sky with it is very natural and easy to do at any skill level. My personal preference is the ones that show rings rather than just a dot, but I have and use both kinds. The way these sorts of finder work is that you look through them and they appear to project an aiming point on the sky. What you look through is a clear piece of plexiglas, rather than en eyepiece like a telescope. This makes it easier to keep your eye relaxed and focus your attention on what you're looking at, rather than the finder itself.

You still have your peripheral vision with these finders, and the view is right-side-up. If you can see the object, you can aim directly at it. If not, you can use a nearby visible star to guide you. For example, the Ring Nebula lies almost perfectly in the middle of two bright stars in the constellation Lyra. If you point your finder at that point, then look through the telescope, you'll see it, even though you can't see it by eye.

This is where finders that project rings rather than dots excel. With rings, you can move a certain distance away from a visible object in the sky to see things in the telescope that aren't visible by eye.

Magnifying Finders

It's possible to locate many objects that aren't visible by eye using a red dot or red ring finder as described above. But it's also possible to find these objects using a good telescopic finder. A good telescopic finder differs from the cheap ones I've warned you away from in two ways:

It is larger, so it has a useful light-gathering ability.

It has a mount that securely holds it in line with the main telescope.

The useless models of telescopic finder included with many telescopes look like tiny little telescopes on the side of the main telescope. They are only about 1/2 inch to 3/4 inch in diameter (12mm to 20mm). They are held on a single metal stalk on the side of the main telescope. They don't collect enough light to show you things you can't see with your eyes well, they have a very narrow field of view, and it's hard to align them with the main telescope but very easy to knock them out of alignment.

If the finder isn't aligned with the main telescope, it's useless.

If the finder shows too small an area of sky, you can't get your bearings and find what you're looking for.

If the finder doesn't collect enough light, you can't see the objects in the sky with enough detail to make them out.

To be useful, a telescope-type finder scope needs to have:

At least 2 inches (50mm) diameter aperture (width across the front lens that lets in light.)

A mount that supports the finder at two points along its length.

It's also nice to have a right-angle eyepiece adapter to make it more comfortable to use, so that you don't have to crane your neck to see through it.

The better finders are like looking through a one-eyed binocular. They show a wide field of view, they have a good light collecting area, they're rugged and solid on the telescope so that you don't have to worry about knocking them out of alignment. They are also easy to adjust to line up with the main telescope, and will stay in place once aligned for a long time and a lot of moves in and out of the house without adjustment. I have one friend who takes his scope in his car to various observing sites and almost never has to adjust his finder scope.

Use One or Both

Many amateur astronomers use both types of finder, each has strengths and weaknesses. They'll use the red dot or red ring finder to get close to what they're looking for, then use the telescopic finder to home in on their object before looking through the main scope. this works best with especially large scopes, with can show very faint objects that would be harder to locate with the red dot finder alone.

For most new amateurs, the red dot or red ring finder will be perfectly adequate by itself. It will be the easiest to learn to use. I have two telescopes on which the Telrad is the only finder, myself. If you see me at a star party, that's what I'll be using to find my way around.

All I Want for Christmas is...a Telescope That Works

2010-11-29T13:07:00.000-08:00

It's the holiday season. Prime time to buy a telescope, either for yourself or someone else. Unfortunately, it's also pitfall season for those getting a telescope for the first time.

Buying for a Youth

You know an intelligent, inquisitive young person. You want to give them a gift that encourages their interest in science, gives them access to the universe for their own study, and gives them a chance to stretch their mind. A telescope is a great choice. Iin astronomy, amateurs are as active in doing real science as the professionals. They may not have first hand access to new data from the Hubble Space Telescope, but there's a whole universe of stuff that pro scopes like the Hubble don't have the time to look at--that's where the amateur astronomers come in.

That first scope can be a blessing--or a disaster. A good scope, even of the most modest type, can be used to learn and grow and do real science. A bad scope can bury an interest in science and convince the poor youngster that they're "no good" at it.

Here are some prior articles I've written that apply to telescopes given as gifts:

If you read no other article, please read
Department Store Garbage Scopes.

Also, at least scan Telescope Mounts, What Not to Buy. It gives some common bad designs to avoid.

You'll also want to know about advertising claims that are misleading. High Magnification: Forget It!" explains why those claims are bogus, and what you should look for (telescopes don't work like microscopes, but advertisers take advantage of people who don't realize this.)

Glance over A Kids' Telescope, if you can.

You may also consider giving a pair of binoculars that are good for astronomy, rather than a telescope. Have a look at Starting Small.

Buying for Yourself

If you're buying for your own use, you'll want to have a look at the above, plus review the articles below:

First Telescope Economics

Don't Buy a Telescope That Doesn't Fit

Want to Test-Drive a Telescope?

Happy Holidays, and may all your astronomy purchases bring happiness and enlightenment.

How to See Through Your Telescope

2010-08-09T21:43:00.000-07:00

When I take my telescope to star parties, to show off the sky to the public, I get two types of people at the scope. One type of attendee approaches the scope, darts their eye toward the eyepiece, then is away again almost immediately.

"Did you see it?" I'll ask.

"Yeah, I saw it," they'll say as they buzz away, as if they're in a hurry to get somewhere.

Yet they'll have been at the eyepiece so briefly that they'll not really have even had a chance for their eye to focus properly. They've glanced at the image like a quick glance at a picture in a book. They saw the light, but not the object itself. They didn't give themselves a chance to see whatever it was I had in the scope, its shape, color, or any detail. Even when I know what I'm looking at, I can't really see it that fast.

The second type of viewer takes their time. They allow their eye to adapt to the view through the scope. Looking at an image in a telescope is not like looking at a TV screen, or a book, or at something that we see without any assistance in front of our eyes. It takes a moment for our eyes to adapt. The second type of viewer gives their eye a chance to adapt to the view.

They actually get to see what's in the scope.

When the object I'm presenting has fine detail to it, I make suggestions to the viewers who are willing to take the time to really look. I ask them if they can see some specific detail, to give them an objective. "Can you see the light yellow bands on Saturn?" "Can you see the dim star just below the brighter star? It's hard to see in the glare of the brighter star." "Can you see the dark area just below the bright nucleus?" And so on. Then I tell them to take their time to allow their eye to relax, since a relaxed eye is more sensitive to detail.

Learning to See All Over Again

When you're learning to use a new telescope, really taking time to learn to see is important to getting the most out of your scope. A lot of it is simple experience, coming from looking at many different objects and types of objects. Part of it is using good practices, giving yourself a chance to get better at it. With time, you'll find that you learn to see more of what you look at. You'll see more detail, and see more of what distinguishes one object from another. The galaxies won't all just look like "gray fuzzies" any more. You'll be able to make out the weather patterns on planets, and so on.

The Downside

The downside to this is that you may find that you notice flaws with your telescope that you didn't notice before. There are some instruments that this may never happen with, the fine ones at the top of the market, for example. But even some of these will show imperfections if they're of a sort that need adjustments to the optical train, like a Newtonian reflector.

Many telescope flaws are easily fixable. But with some telescopes the limitations may be something you can't overcome. In some cases, you may simply find that the scope, while fine for some types of observing, no longer fits your preferences for the type of observing you do.

Remember how I've recommended not to bet everything on your first telescope? This is why. No matter how good your first telescope is, it may not end up fitting your preferences that develop as your observing experience grows. Also, a scope that looks optically perfect to an untrained eye may look very different to a more experienced eye later on.

So be prepared to have your taste in telescopes change. Don't worry, it's a good thing.

Give Your Eye A Chance

Here are some practical things to do to allow yourself to get better views through your scope:

Allow yourself to look long enough at each object.
Make it so that you can relax while you observe.
Read other observer's reports, so you have specific details to look for.
Try observing the same object under different conditions, either by using filters or different magnifications during one session, or on different observing sessions at different times of year or under differnt sky conditions.
Observe reasonably often, if possible. You "forget" if you go too long between observing sessions. If you can do a number of sessions over a short period of a few weeks, then go without for a while, you'll get more than from the same number of sessions spaced out widely in time.

The StellarVue SV115T20 Telescope

2010-06-18T14:16:00.000-07:00

I had an opportunity to attend the StellarVue Dark Sky Star Party this year. (Read my report.) While I was there, I got to experience the sky through quite a few of StellarVue's telescopes, as well as a variety of other scopes.

See the SV115 in the Star Party Picture Gallery!
The scope that had the greatest impact on me was StellarVue's 115mm refractor, the SV115T20. It's a small scope, both in aperture and its physical size. It's small enough to put in a carry-on bag when flying. But the views it provides are far beyond what you'd expect for a telescope of its aperture.

What M82 looked like through the SV115 as best as I can recreate it. The above image has been heavily modified from an original image by Markus Schopfer.

One of the most spectacular views I had through it was M82, a.k.a. Bode's Galaxy or The Exploding Galaxy. I have never seen so much detail across the center of that galaxy through a small (less than 10 inch) scope as I saw in the SV115. I've tried to recreate the view I had in the image above, but it still falls short of what I saw--there was even more subtlety in the center of the galaxy than I show above.

Another impressive view was the entirety of the Veil Nebula. It stood out from the background as strongly as the Ring Nebula, but with all the detail in it that the Ring doesn't have.

Normally, I don't recommend a scope in this price range as a first scope. Even if a first time buyer has the budget for a scope like this, I usually recommend they start with a cheaper scope, then go for the big purchase after they have a year or so of experience. Well, this scope breaks that rule. If you've got the budget for this scope, go ahead and get it. No other scope that you'll buy later will turn this one into a "closet scope." It'll be something you continue to use alongside any other instrument you buy later.

StellarVue SV115T20. Image by StellarVue.

If you don't have the budget for this scope, StellarVue has a line of scopes that range from low cost to high. Each one is exceptional for its cost, and every scope at any price is individually assembled and tested by the folks at StellarVue. There are no scopes from SV that are mass-assembled overseas and shipped here in containers, never to be inspected until the customer opens the box. The extra care is worth a bit extra in cost compared to similar scopes from other manufacturers that don't receive this care.

What Can I See with: 35mm Binoculars

2010-04-22T13:49:00.000-07:00

I have a bunch of different telescopes. They range from 2 inches to 12.5 inches in diameter. But the instrument I use more than any of my telescopes is a pair of 7x35 binoculars.

My binoculars aren't as good-looking as these, but they work the same way.

My binoculars are light, easy to pack along (they take practically no space at all) are easy to carry along even when I'm not observing near my car (when hiking and so on), and they're easy to share with others.

There's plenty that even a small pair of binoculars can be used to observe. And it's not just sort of generally looking around, either. You can do serious observation with binoculars. Not only that, but binoculars are a perfect helper when you're using a telescope, too.

What Can I See?

In the Solar System

The Moon (and features on it),
Mercury, Venus, Mars,
Jupiter and four of its moons,
Saturn and 2 to 3 of its moons,
Uranus, Neptune,
and about 26 asteroids.
Don't look at the Sun!

Seeing asteroids through binoculars can be a lot of fun. In some cases, they move across the sky quickly enough to make tracking them with a telescope over extended periods of observation difficult. They look like small dim stars, but in some cases you can see their brightness vary as you watch them. You're seeing the effect of the rotation of the asteroid when this happens!

Stars

You can see something like a total of 650,000 stars in the sky with a pair of 7x35 binoculars. Now, this is across the whole sky, even the parts you can't see. And, let's face it, not all stars are very interesting. Here are a few of the ones I find most interesting:

Albireo, a binary star in the Swan, one amber star and one blue one.
Cor Caroli, a binary star in the Hunting Dogs, one is bright, the other dim.
O1 Cygni in the Swan, a three-colored triple star
delta Scorpii, in the Scorpion, a sextuple star of which you can see three stars
Herschel's Garnet Star, a deep red star in Cepheus

The top of a car can provide some stability at a pinch.

Star Clusters

Stars tend to be more interesting in groups. There are two kinds of star clusters, "open" clusters are groups of stars that formed out of the same cloud of gas and dust and are in the process of each going their own way in the galaxy. Globular clusters are like mini-galaxies of stars that are held together by the gravity of the stars.

Globulars are called that because the stars form a sort of "globe" shape due to their gravity. They are among the oldest objects in the universe, and probably have something to do with how our galaxy got its shape. Some of them may be the left-over cores of galaxies that merged with out own.

There are about 100 globular clusters that can be observed with 7x35 binoculars. The dimmest ones are very challenging. I have observed about 55 of them through my binoculars, getting more will take a trip to the southern hemisphere or extremely good sky conditions. When I observe globulars, I look at a few things. How is the light distributed across the area of the cluster? Does it have a tight core, with a faint halo of stars around it, or does the brightness taper off gradually toward the edges? Some are very bright out to the edge, then suddenly dim at the edge. I also look at how tightly bunched the stars appear to be, and the shape (compared to a circle.)

Some of my favorites are:
M22 in Sagittarius, which has a large, bright center and misty glowing edges,
M13 in Hercules which is just plain bright. It's center is bright and it fades out gradually.
M4 is large and misty, covering a large area of sky near Sirius, the Dog star.
M80 in the Scorpion is small and tightly bound.
M55 in Sagittarius is small and bright, with a faint haze around the edge.
M2 is big and bright in the center, fading out rapidly to its edges.
M5 is large and has a large central bright area.

Open clusters are often near nebulas, either gas and dust left over from the material they formed from, or other nearby nebulas in which other new stars are forming in our galaxy.
The trifid nebula has a nearby cluster called M21, for example.
In Perseus, the Double Cluster lets you see two star clusters at once.

A long necked bottle is another improvised bino mount.

Deep Sky Objects

Star clusters are one of the various types of so-called "deep sky objects", which includes nebulas and galaxies. One of the most famous lists of deep sky is the Messier list, named for astronomer Charles Messier. He and his associates were comet hunters. They spent night after night looking for fuzzy-looking patches in the sky, trying to find new comets. Often they would see other things that weren't comets. The Messier list was a list they made of things frequently mistaken for comets.

Now the list is far more useful to amateur astronomers as a list of relatively bright things in the sky that are interesting to look at. There are 110 objects on the list, from stars to galaxies to nebulas. All but three or four are visible through 7x35 binoculars (and if you have excellent skies and are a very skilled observer, you might be able to get all 110!)

Man Made Objects

There are a wide range of man-made objects you can see with your binoculars. For most of them, binoculars are the best way of observing them. You can easily see the space station. In fact, as you watch it you can pick out some of its details, such as the solar panels running crossways to the main boom on which it is built. As it moves, the reflection of the Sun will reveal different parts, such as the habitation sections and heat radiators, if you look sharp.

There are also the Genesis habitat test satellites, which are highly reflective. The Iridium satellites can be very bright, and with binoculars you can follow them through the sky far longer than is possible with the eye when they are dim.

Dusk and dawn are the best times for satellite observing, as you are seeing them when it is dark where you are, but they are still in the sunlight. Polar orbiting satellites are visible all through the night.

A walking stick, or tent pole, can hold up a pair of binoculars for astronomy, too.

Sweeping the Sky

One of the best things about binoculars for astronomy is their wide field of view. This lets you look at things that cover too much sky to be seen in a regular telescope. For example, many nebulas cover a large part of the sky, so only a small part of them can be seen through a telescope at any one time. You have to move a telescope around to see it, a piece at a time. With binoculars, however, you can see the whole thing or much more of it. Perseus the Hero and Cygnus the Swan are good constellations to go looking for this sort of nebula.

The Andromeda Galaxy (also known as M-31), is too big to see all at once in a normal telescope. You can see it all at once in binoculars. It covers about five times the width of the Moon in the sky. Under dark skies, you can see its bright heart (nucleus), and the faint cloudy outer parts (the halo.) The edges can be made out in binoculars, where the cloudiness sort of seems to just go away.

And then, there's the binocular's favorite--the Milky Way. With a pair of binoculars you can see the Milky Way like you've never seen it before. Not only can you make out the individual stars, but you can see little knots of brightness in it, and dark patches. The bright areas are nebulas and star clusters buried in the Milky Way. The dark areas are usually dark nebulas that block off the light of the stars behind them.

One particularly interesting area of the Milky Way for binoculars is the area around the constellation of Scutum (the Shield.) This is north and east of Sagittarius the Archer. There are clouds and whorls of stars in this area, as well as cloudy nebulas. With a bit of experience, and taking the time to look with relaxed eyes, you can pick out the details of what you're seeing from the general mass of the Milky Way. The more you learn about what you're looking at, the more interesting it will be to observe. I will often make an effort to remember something that is particularly interesting, then go look it up in a guide to the sky to find out what it was. Later, I can come back and see more detail yet, since I have a better idea of what it is I'm looking at.

Holding Binoculars

In order to see things well, you need to make the binoculars hold still. If they're moving, it's hard to make out what you're looking at and to relax to let your eyes see as much as possible.

How to hold binos in your hands to keep them stable.

By Hand

To hold the binos as steady as possible by hand, bring your wrists close together under the binoculars to form a sort of table for them to rest on from the heels of your palms. Then rest your elbows and upper arms against your body to support them. Take in a deep breath, then let it halfway out and hold your breath. Don't strain to hold your breath, just don't breath for a half a minute or so while you look. Then take a breath, and do it again.

With a Support

Placing the binoculars on something makes them far more steady than you can hold them by hand, and you can breath as you please while you do it. Aside from dedicated binocular stands I've supported my binoculars during observation in many ways. A fairly flat tree branch will do. For objects that aren't too high in the sky there's the roof of a car. A long-necked bottle will often sit nicely between the barrels of the binoculars to act as a simple "monopod", or a walking stick can be used.

Halfway In-Between

In some cases you can't rest the binos somewhere and see what you want to see. Then holding them by hand while resting your wrists and the backs of your hands against a steady object will have to do.

Binoculars into Space

Binoculars are great for astronomy, they have a wide field of view that gives a "space walk" experience, they're easy to use, find things with, and take along. They can also help you find things so that you can look at them through a telescope afterward.

They're what I recommend for starting stargazers who are thinking about getting a telescope. It's possible to do serious observing "campaigns" with binoculars, like collecting as many globular clusters or galaxies or Messier objects with them as you can. Using them is great training for learning to see objects in the sky that will pay off with a telescope later. They're cheap, and useful for things other than astronomy.

Check out some of these books on using binoculars for astronomy:

A Kids' Telescope

2010-04-02T15:55:00.000-07:00

One of the most popular reasons to buy a telescope is to advance a youngster's interest in science and the world around them. Unfortunately, this is also one of the things that leads to the sales of department store junk scopes. Junk scopes convince kids that they can't handle science, that it's hard and frustrating and not worth the effort. If you want to drive them right back to video games, get them a junk scope.

There are some decent scopes out there, though, and some things you can do to increase their interest in using and having a telescope.

Meet the Astronomers: Star Parties

Find a local star party and take your favorite youngsters to it. There they can meet amateur astronomers, and sometimes professionals as well. They can also see the different types of telescopes around, and get a chance to talk to their users and possibly even try one out.

Don't think that all the astronomers at star parties are some sort of hard-core astronomers with expensive equipment, either. At the star parties I take my scopes to, the astronomers range from beginners who've just got their first scope to those of us who make our own and have been showing the sky to the public for decades. The equipment varies from hand-me-downs to high end commercial equipment. But the hand-me-downs and inexpensive scopes are represented there alongside all the rest.

Preparing for a Telescope

There are few things as frustrating as having a telescope and not being able to see something through it. No matter how fancy the electronics are, the user still has to know something to get the scope to point at things.

For a first scope, I recommend going without electronics.

Next, the kid should have a resource to help them learn they way around the sky. I recommend both software and something in writing they can take out in the backyard at night. For software, check out the free programs like Celestia, Stellarium, or KStars for Linux.

For written resources, a good start is one of the annual specials from the major astronomy magazines like Astronomy or Sky & Telescope. Both also have web sites with a variety of resources, like star charts that can be printed out. Another good resource would be a beginner's star chart, or a book like The Stars by H.A. Rey, or his other book Find the Constellations.

With some basic information, kids can make use of a good telescope once they have one.

Not a Telescope

One thing to consider is getting something useful for astronomy that isn't a telescope. I usually recommend binoculars for beginners. Not only are they useful for astronomy, they can be used for a range of other purposes, like bird watching or sports events. They don't take much skill to use well, and they are still useful even when a telescope is obtained later. I use mine to help find things with my telescope that I can't see directly with my eyes.

A Telescope

If you still feel a telescope is the best way to go, there are some things you'll want to look for in a scope for kids:

Steady Mount: If you can't keep the scope on it, you can't see it.

Rugged: Because kids aren't always careful.

Small: If they have to ask for help to lift it or move it, it doesn't feel like it's theirs.

Simple: They should be able to use it and understand it without help.

A great way to get a scope is to ask around at an astronomy club or star party. There are usually more telescopes than astronomers, as we astronomers tend to end up as "rescue homes" for other people's "closet scopes."

Here are a few commercial scopes I think can work as first scopes for kids, if you end up buying one:

The Orion Starblast and Funscope models are fun and easy to use. They come the closest of anything on the market to what I consider a good kid's scope. A friend's son gets good use out of one.

Orion Funscope

Orion Starblast 6"

Orion Starblast 4.5"

The following are more along the lines of traditional starter scopes, and will work well for a kid at about 12 years old and above. They are similar to the ones my daughters built.

Orion Skyquest 6"

Galileo 5"

Skywatcher 5"

Ongoing Support

Remember those star parties? Well, if you're not an astronomer or not in a position to be around while the kid is learning to use the scope, you might get them a year's membership to the local astronomy club and make sure they can get to meetings. You will also want to check out the Astronomical League. They have observing programs, a quarterly magazine, and scholarships.

A lasting connection to others with an interest in the sky is the most important astronomical tool a kid can have.

Make Discoveries with Your Telescope!

2010-03-29T15:58:00.000-07:00

Don Machholz has discovered his 11th comet with an amateur telescope. This last one, with designation "C/2010 F4", was discovered using his 18" diameter Newtonian telescope. His tenth comet was discovered using a 6 inch telescope from his back deck.

It doesn't take anything special in the way of a telescope to do astronomy. If you're interested in comets, and possibly hunting for them yourself, check out Don's website at http://www.thecomethunter.com/. There's a whole bunch of info there, including one of Don's books, "A Decade of Comets", and a spreadsheet for comet-hunters.

Don's telescopes are very simple, but very effective. What he accomplishes using them is a result of planning and skill, not fancy expensive equipment. Check out his site for yourself, there's a lot there on many aspects of amateur astronomy.

What Can I See With My Telescope Books: #2

2009-07-30T03:30:00.000-07:00

In my previous article on this subject I recommended The Night Sky Observers Guide, Vol. 1 and 2 as great books to find out what you can see in the sky with any particular telescope.

Now I'd like to recommend the book I use most for figuring out what I can expect to see through my scope, or somebody else's:

This book doesn't have finder charts, like the other one, but it doesn't suffer for it. the descriptions given of the objects and how they appeared in different telescopes are wonderful. They give you a clear idea of what to expect. The descriptions do use astronomer terminology a bit more heavily than the other books. The terminology is pretty simple to learn for anyone with an interest in astronomy, and there's a guide in the book.

All the constellations are here in one volume. The sky is covered from Polaris down to the sky as far south as it can be seen from Flagstaff, Arizona.

The book is definitely geared more toward the "serious amateur" than the Night Sky Observer's Guide. It doesn't have breakouts of particularly interesting objects, nor does it have illustrations of any objects, except a few special cases. However, this also makes is smaller and lighter, and everything is in one volume. It is far more usable at night under the sky.

It covers telescope sizes from 60mm on up, but the focus is definitely on telescopes 8 inches (200mm) and larger. Though there is good coverage for 6" (150mm) scopes.

What Can I See With My Telescope Books

2009-07-28T15:17:00.000-07:00

About the most common question I hear from new telescope owners, or those looking at buying a specific model, is "What can I see with this telescope?"

There are some books that are designed to answer just that question. First, there's the Night Sky Observer's Guide, Volume 1 and Volume 2 by Kepple and Sanner.

These books are extremely comprehensive. They have an introduction to each constellation that lists the showpiece objects of that constellation. They list them both as the best deep sky objects and the list the best binocular objects, which often make excellent objects in telescopes of any size. They provide an overall orientation chart for each constellation, and several finder charts for each constellation with individual objects marked relative to the nearby stars.

The range of telescopes covered goes from 60mm (2.4 inches) of aperture on up to 18 inches and beyond. Descriptions of the objects give you an idea of what the object should look like, and how well it will appear in your scope. Many of the objects have drawings and photos to give you an idea of what the object will look like, as well.

My only complaints with these books is that they are heavy, and that the finder charts are often confusing. The orientation of the finder charts varies, the orientation is often different from their parent chart. This gets confusing whenno reference for direction is given with the chart--you have to go from chart to chart, often across several different pages, to get an idea of what the orientation of the small chart is compred to the big one. In the dark with a red flashlight this gets to be a pain. It's better to use the books at home before observing, put the likely sounding objects on a list, then use your favorite star charts to locate them out under the stars.

Volume 1 covers the Autumn and Winter constellations. That is, it covers those constellations that cross the zenith at midnight during northern hemisphere autumn and winter. Volume 2 covers the Spring and Summer stars. Specifically:
Volume 1: Autumn and Winter Constellations:
Andromeda, Aquarius, Aries, Auriga, Camelopardis, Cancer, Canis Major, Canis Minor, Cassiopeia, Cepheus, Cetus, Columba, Eridanus, Fornax, Gemini, Lacerta, Lepus, Lynx, Monoceros, Orion, Pegasus, Perseus, Pisces, Piscis Austrinus, Puppis, Pyxis, Sculptor, Taurus, Triangulum

Volume 2: Spring and Summer Constellations:
Antlia, Aquila, Bootes, Canes Venatici, Capricornus, Centaurus, Coma Berenices, Corona Australis, Corona Borealis, Corvus, Crater, Cygnus, Delphinus, Draco, Equuleus, Hercules, Hydra, Leo, Leo Minor, Libra, Lupus, Lyra, Microscopium, Ophiuschus, Sagitta, Sagittarius, Scorpius, Scutum, Serpens Caput, Serpens Cauda, Sextans, Ursa Major, Ursa Minor, Virgo, Vulpecula

Constellations with particularly attractive or interesting stars have those listed at the start of each constellation's chapter.

There's another book I really like for finding out what I can see that I'll cover in my next posting.

Starting Small

2009-07-03T12:27:00.000-07:00

While a telescope certainly has a "scientific" panache, a good way to start observing is with a pair of binoculars. Very nice binoculars can be bought very inexpensively these days, pairs that used to cost hundreds of dollars are available at sporting goods stores for under a hundred, often less than $50.

A good starter pair should be useful for things other than astronomy. That way you'll get more use out of them. They don't need to be huge, and they shouldn't be too high of a power of magnification.

Numbers on the Binoculars

The numbers used to describe binoculars are usually written something like "7x35" or "15x60". The first number is the magnification of the binoculars. I recommend a magnification of 7x or 8x, certainly 10x or less unless you're expecting to use them on a tripod all the time. Higher magnifications can't be held steady enough to use hand-held. I have a pair of 20x binos that don't really work when hand-held.

The second number is the size of the area that lets light in at the front of the binoculars, the front lens, in millimeters. So a pair of "7x35" binos has front lenses that are 35mm across. A pair of "8x50" binoculars has front lenses that are 50mm, or just over 2 inches, across. The larger the second number, the more light the binoculars collect. So all else being equal, a pair of 50mm binos would be better for astronomy (where we're looking at dim things_ because they collect more light from what you're looking at than a pair of 35mm.

But, if this number gets too big, the binoculars get larger and heavier. That means they're harder to hold steady, and they're less likely to get packed along when you go somewhere. I have pairs that are 35mm and 60mm, and the 35mm pair get used a lot more often than the 60mm pair just because they're more convenient.

So for starting out, I recommend something from 7x35 at the low end to something like 8x55 at the high end.

Avoid binoculars with "ruby" lenses or coatings. These are good for getting rid of glare in the daylight, but we aren't worried about glare and we want to get all the light we can.

Other than that you can get whatever features you are willing to pay for, but remember that you'll be looking upward--so make sure the binos will stay focused when you do that--and you don't want extra features getting in the way of the basic use of the binos.

What can I see?

Binoculars can see details on the Moon. You can also see the planets, but you won't see them as disks, just as colored points of light. You can see moons of Jupiter and Saturn. Binoculars are good for looking at globular clusters and star clusters, and you can see several bright nebulas, like the Orion Nebula. A few of the brighter galaxies can also be seen as fuzzy patches in the sky.

Even with a telescope, binoculars make a good adjunct. I use mine to help me find new objects in the sky for my telescope. I'll use the binoculars to get my bearing on where the new object is (when it's something I can't see by directly looking at it with my eyes), before I try to get it in the scope.

Department Store Garbage Scopes

2008-12-06T09:03:00.000-08:00

It's the Christmas shopping season, and a trip to the mall last night showed me that everyone is putting awful telescopes out on prominent display once again. Every year I see these abominations set out to lure hapless buyers into parting with their hard-earned cash in the hopes of getting someone a gift that'll mean more than a Nintendo game.

For example, I saw one that the hucksters say:

"Telescope is ideal for the young stargazer.

Great for star tracking, viewing wildlife, sporting events and more. Mirrored diagonal eyepiece. 24½"L. Durable, lightweight aluminum construction. Assembly required. Ages 13 and up."

It's terrible for star tracking. It can't track stars. It's got a cheap, awful photo-tripod style mount that makes it almost impossible to get any particular star (or planet, or even the Moon) in view, much less track it! Sporting events? Who's going to haul something like this, with its narrow field of view and stand and all to a game? Wildlife? Better hope it's sessile, because if it moves while you're trying to get it into view with this you're going to have to work at it twice as long.

If this scope is in your price range, get binoculars instead. There are many nice models of 7x35 binoculars and even some 7x50 binoculars available at the same price or lower than this terrible telescope. Binoculars really will be useful for sporting events and wildlife, and guess what? They'll be better for astronomy, too. You can get a nice pair of binoculars for about half the price of the above telescope, and spend the rest on a copy of Phil Harrington's excellent book, Touring the Universe Through Binoculars. It's a fine introduction to practical astronomy suitable for bright kids age 10-12 on up, or, for younger readers try H.A. Rey's The Stars, a New Way to See Them.

The reason stores put out items like the abominable scope above is simple. They sell. It's not like the people who stock the stores are really out to sell you something useless--they're probably just as unknowing as the people who make the mistake of buying them. Don't encourage them to keep stocking stuff like this. Pass it by.

And look at some of my previous posts for what to avoid in telescopes in higher price ranges. There are losers in every price bracket that you don't want to saddle someone else with. Don't kill a kid's incipient interest in science by getting them a bad instrument. Too often they'll blame themselves for not being able to use a useless device.

Microscopes as Gifts

While we're pointing out bad instruments for kids, let's talk microscopes.

If it has a plastic body, it's useless. Light gets through the plastic and ruins the image. If you're lucky, you'll see your eye. Chances are you'll see nothing.

If it has only high magnifications (100x and higher) it's useless. That's too high to use unless you have a really good instrument and an experienced user. I use a microscope for work, and I use 25x and 40x almost all of the time. A beginner's microscope has to have magnifications under 100x available. Optimally, the highest magnification on a triple turret scope for a beginner should be 100x or below (e.g. 25x/40x/75x or 40x/60x/100x. You get the idea.)

And it needs to have a metal body. So the light doesn't get in between the eyepiece and the object lens.

And they'll need a light, but it doesn't need to be one of the hot high intensity lamps so often sold for microscopes. The little mirror will be pretty much useless to a beginner. But a nice little white LED light (like a brighter model of book light) will work well for under the stage of the microscope (and it won't cook the specimens) and a handy table lamp without a shade or a desk lamp will illuminate opaque objects from the top.

And it doesn't need to cost a fortune.

Cut to the Chase: Larger Scopes

2008-09-02T22:25:00.000-07:00

So a scope of 5 inches aperture or less isn't going to do it for you?

Never fear! There are a lot of good larger scopes to be had.

Now, I'm not going to recommend going out and buying that 18 inch monster as your first scope, even if you can afford it and possibly could even make use of it. Even if you end up getting one as your second scope, it better to start smaller and work your way up. After all, think of how you'd feel if you went ahead and got it, then six months later decide your true love in telescopes is a high performance large aperture refractor?

Get a good all-around scope before you start getting specialty scopes. If astronomy is really the hobby for you, your first scope won't be your last. If you end up just being a casual astronomer, having a good all-around scope that is convenient to take out a few times a year is far more valuable than having a complex monster you've never got the time and energy to get under starlight.

So I recommend a six-inch or eight-inch reflector for a first scope. In general, I recommend these more highly than the portable scopes I described earlier, but which one is for you depends on your tastes and what circumstances you expect to be observing under.

For a mount, I recommend a Dobsonian mount more highly than an equatorial mount. The Dobson mount is easier to use and set up, lighter, easier to pack in a car or carry in and out of the house or garage. With a Dobsonian there are basically only three things to move: the base, the telescope tube, and your accessories box. Setup usually only involves setting the tube in the base. Then all you have to do is take the cover off the end of your tube and the plug out of the eyepiece hole, put in an eyepiece, check your finder's alignment, and off you go.

You'll also want to learn to collimate the scope, but on a well made scope you shouldn't need to do this often. To learn this, find another amateur who teaches this, or get someone at the store you bought it from to teach you. If nobody at the store knows how well enough to teach it in a simple fashion, find another store. It's the sort of thing that is easy to teach in person, but sounds horribly awkward and complicated in print. So don't be scared, it's really not that hard. My daughter learned to collimate her own scope when she was 10. I think half the problem is the word "collimate." It sounds so technical and complex. It just means lining things up inside, and you can tell if they're lined up by looking at them, just as you can tell which way a car is turning by looking at the front wheels.

Now, which telescope to buy?

I don't have any specific recommendations, though the scopes from Orion and Meade of this type are nice and attractively priced, in my experience. There are lots of folks who own these scopes, go to the forums where they hang out and ask them their experiences (as well as for other brands you may consider.) They can usually tell you what additional accessories you should expect to buy right off (for example if you'll need a better finder, or a supplementary eyepiece to the one included) as well as any tweaks you should expect to make to the scope "out of the box."

Since the manufacturers update their designs frequently, any such statements I could make here would probably be out of date by the time you see them.

One point I should make is not to underestimate the six inch scope. A well made six inch scope with good optics will outperform a so-so eight inch scope. I know this for a fact. My daughter's six inch is a far better scope than an older eight inch commercial scope I own. Her little six inch f/9 telescope gives clearer views, better contrast, and more detail than my big fancy-looking eight inch telescope--at least as it came from the factory. Once I saw how much better my daughter's scope was, I made some modifications that have improved it to where it's about on a par on bright objects and slightly better on objects that are dim enough to be marginal in her scope. I plan on doing a major overhaul on the scope someday. It effectively won't even be the same telescope when I'm done with it. Among other changes I'll be re-grinding the mirror and putting it in a new tube. That's how major I'm talking.

In a six inch I can highly recommend an f/8 or f/9 scope. For an eight inch an f/6 or f/7 scope will be good. You can get a "faster" scope (scopes with a lower f/ratio number are called faster because the light comes to a focus in a shorter distance, thus "faster" than a scope with a higher number. An f/6 scope is "faster" than an f/8 scope.)

Check with current owners before buying, and get a chance to play around with one, too. It should move smoothly along a diagonal line. It should stay put when you stop pushing it. You should be able to point it at something far away, tap the tube sharply, and it should still be pointed at the far away object (when looking through the eyepiece at a magnified view, of course.) It should have the eyepiece at a height that you can see through it both when it's pointed straight up and when it's level with the ground without breaking your back or neck. Uncomfortable stances aren't going to help you see the sky, they're going to leave you inside with an icepack and keep you from taking the telescope out again because using it hurts!

Observing should be reasonably comfortable. You can use a step stool or an observing chair, but you shouldn't have to for this first scope. It should be usable from at least an angle pointing up only about 20 degrees (about the slope of a low roof) to straight up without you needing any help. If the telescope's tube can rotate easily in the cradle without a lot of fuss and without throwing it way off balance then this is a big plus for comfort. Some scopes come with two sets of "ears" or altitude bearings so that you can rotate the tube 90 degrees for different eyepiece angles. My preference is having the eyepiece set at an angle of about 45 degrees from the ground or even a little higher when the tube is in a flat position. This lets you see into it at low angles without destroying your neck vertebrae, and when it's pointing straight up the eyepiece is going to be horizontal no matter what angle it's at when lower.

Check stability with the scope in different positions. Make sure you can adjust the balance of the scope tube. If the tube doesn't slide in its cradle, you may need to add some sort of counterweights--see what current owners say. There are some cheap and simple ways of doing this. One of my favorites is weighted bags that grab onto Velcro strips placed on the telescope tube.

In my case, I have the luxury of building my own scopes, so I always make the tubes so they can slide back and forth with respect to the ears and rotate around their axis to bring the eyepiece to a convenient angle. Most commercial scopes don't do this, though, because it would cost more and most people look at price, not at usability features like this. If the market demands it, they will build it, but if it doesn't, they'll build for lowest price. Unfortunately all too often the market doesn't know what it's missing when it goes for lowest price.

And, as mentioned before, go to a star party and see what others are already using and talk to them about them. There's the added advantage that if you get the same scope as someone else in your area, you'll always have someone else to keep you up on good ideas for your scope, accessories, and give you an idea of what you can get out of your scope. And you can do the same for them.

First Telescope Economics

2008-08-31T22:47:00.000-07:00

How Much Should I Spend?

This is a question for which there is no one answer, because different things are going on in the minds of each person who asks. For some, they have a good chunk of money set aside. For others, they don't have as much of a budget and they're afraid the answer they're going to get from an astronomer is going to include a bunch of extra foo-foo that they don't really think they need since they perceive their own needs as modest, hopefully to be met by the modest costs they've seen on junky department store scopes and bargain spotting scopes from sporting goods stores.

Money to Spend

If you're in the first group--you've got money and you're prepared to pay for quality since your time and the experience are important enough to you to pony up for it--my advice is usually to force yourself to spend less than you're prepared to. First, you're not going to know exactly what all you're going to want and need at the outset. So you're going to buy more bits and pieces later when you have a better idea. Second, you don't know what sort of an astronomer you're going to end up as yet--there are lots of sub-hobbies within the astronomy hobby--so save your big bucks for the more specialized instruments later. Plan to spend half to two thirds of your planned budget on some quality pieces of equipment that will still have a place in your home even when more comes later.

Keep It Cheap

If you're in the second group--you'd like a telescope but even the prices of the ETXs and Stellarvues I recommend sound like an awful lot--my advice is don't break down and buy a cheaper piece of junk then hope that everything will turn out all right. It won't. Even big-name manufacturers like Meade and Celestron turn out complete junk. I have dozens of friends who own these scopes, I own a few, some I intercepted them on the way to the trash can. Do I have them because they work? No, I have them because I rip bits out of them for other uses. As telescopes they're useless.

Let's look at the economics of a telescope compared to another luxury item. Let's compare it to the cost of a Nintendo system.

A Nintendo Wii with a common package of accessories (extra controller and nunchuck, recharger/rechargeable battery packs) is going to cost you just about $400. Then you're going to want more than the pack-in games to play, so if you go with one older title and a newer one you're looking at another $70-80. Then you'll probably end up with some other annoying cost before you're playing, like a new power strip or video cable. So the total to get from the store to playing games is going to be about $500.

I ended up paying about $650 by the time I got my Wii in place and all sorted out. You can do it cheaper--at first--but once you've got all the bits you want to really have the thing working you'll just have spread out the $500 or more in cost over more time, not really reduced it.

You'll be able to buy games for the Wii for the next five years or so in the stores. After that, it'll be as dead at retail as my Gamecube and my Atari 2600. If you buy three games or so in the stores each year, you'll be spending another $80-150 per year. If you buy games on the Wii itself across the internet, you'll be spending $5-25 per game. If you're a cheapskate like me, you'll be able to keep games down to $50-100 a year by buying them second hand, but you'll also spend more on aspirin when dealing with scratched or otherwise non-working disks.

By contrast, if you spend about the same on a telescope, or even cap it at only 80-90% of the cost of a Wii, you'll have something that you don't need the stores to supply you with new content for. My newest scope is about the age of my Gamecube. It's a home made scope that cost me about $250 to build. That's about the same to build as I paid for my GameCube as a used system package with extras.

The Gamecube collects dust in my entertainment center today. The telescope is still the main telescope I use both for my own observations as well as at star parties where I show the sky to the general public. The Gamecube hardly gets used any more. About 1500 people have seen the sky through my telescope in the past year. The telescope doesn't go out of date.

A good Stellarvue scope, like the SV80, goes for about the same as a Wii package once you add on one of Stellarvue's nice mounts. You can start using it right away. If you spend about the same on accessories for it each year as you would for a Wii, you'll have all the accessories you could ever need within the first couple of years, and you can stop buying. Plus, unlike the videogames, you will be able to use those accessories on other telescopes. I still use every eyepiece I've ever owned.

I buy new eyepieces every five years or so. I keep buying new ones because I keep building telescopes that take advantage of features of eyepieces I don't already own. If I didn't keep making new scopes, I would be perfectly happy with the eyepieces I already own.

Cheaper telescopes are available. They're unusable as they are. Once you've spent the money to make a working telescope out of them you've spent as much as you would on a good scope. But chances are you're not going to. Instead you'll take it out, have it not work, and get discouraged. You'll probably blame yourself for not being smart enough to figure out the telescope. Nothing could be further from the truth. The problem isn't you, it's the scope.

A good scope is as easy to use as a pair of binoculars. You can point it at what you want to see, you can keep it pointed at it, and you can see it. It won't drift or wander off target. It won't frustrate you with a computer that you can't get figured out or that likes to drive the telescope right into the tripod. It won't make you break your neck and strain your eyes trying to figure out how to get something into a tiny little finder that's poorly positioned and that you don't even know if it's lined up with the telescope.

So if you don't have enough for a good telescope now, save up and get a good pair of binoculars. Learn the sky with those and your eyes with the help of a couple of good astronomy books. Contact a local astronomers' group. You can get scope bargains there from folks who are upgrading, and you'll have a chance to try out different scopes and learn to use them from experienced users.

Then when you buy, you'll know what you want and need, and have contacts to help you get the best prices.

Cut to the Chase: Portable Scope

2008-08-28T12:01:00.000-07:00

I'll post more articles in the future about what you do and don't want in a telescope, but for now I'll give some specific recommendations. First, I'll recommend some scopes that are especially portable.

These are good if you need something small and easy to take with you, or you have very little space for storing a telescope between observing sessions.

First, I recommend the Meade ETX series Maksutov-Cassegrains. These presently include the ETX-90, ETX-105, and ETX-125. Different versions have different letters after the model name to indicate what features that specific model includes. I own an ETX-90RA, one of the earliest models. It includes a clock drive, but no guidance computer or other electronics. Newer models have replaced the RA, so these aren't available new any more.

On these, I recommend learning to use them without having to have the computer guide the telescope. Simply use the hand controller as you would a set of mechanical slow motion controls for pointing the telescope at first. Later, learn to use the computer drive as a clock drive to keep the telescope on an object once it is in view. This will require learning to do a "north alignment" on the telescope.

I don't give the instructions for doing so here since different versions of the computer-controlled ETXs use different software versions that do it differently. Also, I don't know how to do it specifically, I only know it's possible.

Once you've learned to align the scope, you should be able to use the computer to direct the scope toward objects as well. But it will be easier to learn how if you're already familiar with the objects you direct it toward while you're learning how to use the computer. So if you've already learned how to find some objects on your own without the computer, you will know whether the computer is doing what you want when you are figuring out how to use it.

For goodness sake, whatever you do, don't expect to invite a bunch of people out to see the sky on the first night you take the telescope out. There's nothing worse than trying to learn how to use the computer while a bunch of people are waiting on you to show them amazing things in the sky, especially if you don't know Altair from Antares! Expect to spend some time on your own figuring things out, and expect nothing but a list of questions from your first experience.

Set things up inside in the light first so you can learn the controls and familiarize yourself with the menus. Then go into the yard someplace where it's easy to go back inside and refer to a good website (like Mike Weasner's excellent ETX site) to find out why things aren't working the way you expect.

Once you've had a couple of successful sessions on your own, you'll be ready to invite others over for a look.

Even better than the ETXs, since they don't have computers on them, are the wonderful wide field refractors made by Stellarvue. These are not the refractors you see in discount stores. They're a whole different animal. Well made, easy to use, high performance. They come in a number of different packages with mounts and accessories. They can show you things you didn't know you could see in a scope that size. The images I've seen in every Stellarvue I've looked through have been excellent. The price of an SV80 is comparable to the price of an ETX, but the SV80 comes with a lot more "fit and finish" if you know what I mean. And the Stardust Blue coatings just emanate a feeling of "classy."

Plus the Stellarvues come with an excellent case. I paid over $100 extra for a nice case for my ETX, since all it came with was a cardboard box with a styrofoam insert.

You can get them with a computer controlled mount if you insist. ;) But I'd recommend learning to use the scope without a computer, first. Besides, when you've got such a fine little scope in front of you why let a computer get between you and the sky? (You can always add it later by upgrading your mount.)

What's nice about scopes this size as a first scope is that even if you get a larger scope later the small scope won't just become a dust collector. There'll be plenty of times when the big scope isn't convenient to have along. A small scope packs along easily. I have a large pair of binoculars that used to come with me when I travelled. Now my small scope does. I actually got my small scope after I got a larger scope. I now have two larger scopes, I'm building a third and fourth, but my light, little, easy to pack scope will never go unused. I even use it at home when I don't have enough energy to haul the big scopes all the way to the patio.

For accessories, you're going to want to get a good, solid, easy to use travel case. The Stellarvues have you covered here. For ETXs I recommend the after-market case made by JMI. I picked up a closeout/overstock case from them for a discount, and I love it. The Meade hard case is pretty good, too, but I have a preference for the one from JMI. The finder that comes with the ETX needs replacing, too. The little telescope thing represents everything I hate in commercial pack-in finder scopes. Get a nice red-dot finder or a Telrad. Granted, the Telrad is almost as large as the scope, but believe me the scope's not worth a darn if you can't get it pointed at what you want to look at. The

Stellarvue comes with a red dot finder, so once again, you're already covered at no extra expense. Plus the Stellarvue has a wider field of view than the ETX, making it easier to get objects in the eyepiece.

I'll post another article on the economics of a scope purchase, then I'll post my recommendations for a larger first telescope.

Telescope Mounts: What NOT to Buy

2008-07-14T11:17:00.000-07:00

There are some telescope mounts that are consistently inferior enough to others that it's safe to say they should always be avoided for an astronomical telescope:

The Ball Joint, or Ball-Head Mount

These do a poor job of holding the scope, and even if they have a locking screw, it's not possible to point the telescope accurately or to move it to compensate for the motion of the Earth. In some cases a ball joint may be usable for a camera piggybacked on a telescope (on a good equatorial mount) but it's not adequate for any sort of telescope used for astronomy, even small ones. Personally, I would avoid even low-power spotting scopes that come with this type of mount.

Camera-Style Tripod Mount

Again, these aren't adequate for an astronomical telescope. Pointing them at what you want to see is way too difficult. Trying to compensate for the Earth's motion is nothing but frustration. These mounts are OK for cameras, binoculars, and small spotting scopes that give about 20-25 powers of magnification used for terrestrial purposes. They're not well designed for viewing at high angles, so they're not all that useful for astronomy with any instrument. With binoculars they're tough to use because you have to lean forward over the tripod to get your eyes up to the eyepieces. It's not a comfortable way to look through binoculars, and if you can't relax and enjoy the view you're not going to enjoy astronomy.

Cheesy Fork Mount

There are good fork mounts. They are solid, provide smooth motion, and hold the telescope on what it is pointed at. The fork mounts used on most Schmidt-Cassegrain and Maksutov telescopes are quite good.

And there there are monstrosities like the one pictured above. These are still common on many small inexpensive telescopes. They don't move smoothly, they have slack areas where the scope flies through and tight areas where the scope only moves with dificulty, they don't hold the scope in place even if they have impressive-looking slow motion or other support bars. They're junk. If you've already got a scope on one of these, look at retro-fitting it with a nice homebuilt Dobsonian-style mount or some other good mount suited for the telescope.

Mind Killers

If you want to kill a kid's interest in astronomy and science, buy them a telescope on one of these mounts. If you want to convince them (or yourself) that you're incompetant, and that astronomy is difficult, march right into your local camera shop or "Mart" store and pick up a telescope mounted on one of these.

Some newer mounts have lots of fancy molded plastic around them to hide the fact that they are still one of these cruddy mounts underneath. Lots of little refractor telescopes come on a mount that has a bulgy plastic clamp that goes around the telescope and big plastic handles on the motion controls. It's still just a camera mount.

Don't be fooled into buying one of these. No telescope at any price is a bargain when it's sold on one of these. It's not worth buying and thinking that maybe you'll get some light use out if it and upgrade later "when you get serious." You'll never get started with one of these.

Remember, the mount is more important than the optics of the telescope itself. So-so optics on a solid mount will give you far more use and enjoyment than excellent optics on a lousy mount. When you go shopping, don't ask about magnification, don't ask about aperture or light-gathering power, don't worry about accessories. There are three things you want to know about: The Mount, The Mount, The Mount. If you've got room for 4, I'd recommend staying away from telescopes that use .965 size eyepieces. It's often a sign of a cheap, useless scope. Go for something that takes a 1-1/4" eyepiece. After you find one on a good mount.

Don't Buy a Telescope That Doesn't Fit

2008-07-09T20:50:00.000-07:00

In my post What Can I See With My Telescope I talked about how much detail and what sort of objects you can see with different sizes of scope (the size being measured as how big the light collecting area of the telescope is, like how big the main mirror or lens at the front is.)

The big scopes give the best views. So why not just recommend everyone go out and buy as big a scope as they can afford?

-You have to be able to lift it.
-You have to be able to store it.
-It will probably have to fit in your car.
-You may not want to have to use a ladder to get to the eyepiece.

My recommendation for a first scope is usually a 6" telescope, though anything from about 4.5" to 8" can work. But before you buy any scope, find out its dimensions and weight. Then:

Figure out whether you can lift a bulky, unbalanced weight that weighs as much as the scope without injury or other safety problems. You may be able to lift it, but are you going to have to take it up and down stairs, for example?

Figure out where you're going to store it. Is the space big enough? Are you going to need anything extra to protect the telescope while it's stored? E.g. a cover or carrying case may be required to keep off dust, sunlight, or protect it from damage. What effect will that have on space requirements?

Will it fit in your car alongside whatever else you will be taking on observing sessions away from home? Plan on an ice chest, chairs, accessories box, a few books and magazines, the other people who'll be coming with you, sunscreen, possibly camping equipment and so on.

How high is the eyepiece from the ground? How wide is the range through which it moves? Will you be able to observe without a stepping stool or ladder? Will you have to bend over at an uncomfortable or painful angle? If you plan on observing while seated, will you be able to do so for objects in very different parts of the sky? Find out the measurements for the scope you're interested in (if they're not posted, check in to a forum for that manufacturer's telescopes and ask.) Then break out the tape measure and mock it up somehow to see how the scope measures up against you (and any other potential users of your scope.)

If you're going to need a step stool or ladder for the scope you want, make sure you plan space for it, too!

What Can I See With My Telescope?

2008-07-06T17:00:00.000-07:00

Here are some representative objects, and what they look like, with different instruments (telescopes, binoculars.)

7x35 Binoculars
Planet Jupiter as a bright orange or yellow spot, and 4 of its moons which look lie stars in a row.
Planet Saturn as a bright yellow dot, and its moon Titan, which looks like a star.
The Hercules Cluster (M13) as a fuzzy patch.
Andromeda galaxy (M31) as a large fuzzy area, more condensed at the center.
Alcor and Mizar as a double star.
Herschel's Garnet Star as a dark red star.
Trifid and Lagoon nebulas (M20 and M8) as dim fuzzy patches (more detail under dark skies.)
Orion Nebula (M42) as a light, foggy patch.
Some detail can be seen on the Moon.

60mm Refractor Telescope
Saturn and its rings are clearly visible, along with 3 moons that look like stars.
Jupiter shows a disk with bands, 4 moons appear as stars nearby.
Bright globular clusters like M13 and M22 can be resolved into stars at the edges.
Some detail appears in the bright nebulas like the Orion nebula, Lagoon and Trifid nebulas. They look like wispy cloudy areas. The "Trapezium" appears in Orion, whether it resolves as 4 stars depends on the conditions and the quality of the telescope.
Uranus and Neptune can be seen as colored dots.

20 x 60 Binoculars
At 20x these binoculars require a stand of some sort, you can't hand-hold binoculars over about 10x still enough to see much. I recommend a parallelogram mount.
The planets Jupiter and Saturn don't show a disk, but they and several moons are visible, as are Neptune and Uranus.
Detail of craters and mountains can be seen on the Moon.
Andromeda galaxy shows a difference between the nucleus and halo areas.
Bright nebulas show some detail and some pale green color.
The Moon shows some detail in craters and mountains.

90mm to 4.5" Telescope
Planets are similar to what is seen with a 60mm scope, slightly more detail in Jupiter's bands and a better chance of seeing bands on Saturn. You can go to higher magnifications with these scopes than 60mm (up to about 200x max.)
Nebulas show a lot more detail, trapezium is easy to split into four stars. You can see almost all of the Messier list, all of it under excellent conditions with good optics. The galaxies typically appear as dim fuzzy patches. This size of scope really opens up the heavens for a casual observer, and makes a great starter scope for a dedicated observer, as well as a travel scope for those who've upgraded to larger scopes.

6" (150mm) Telescope
You can see the shapes of galaxies that appeared only as dim patches in a 90mm/4.5" telescope, but no arms or dark lanes yet. The bright nebulas all appear as beautiful showpiece objects. Globulars and open star clusters are very nice, and a 6" does a reat job on lots of multicolored binaries. The 6" makes a good portable all-around scope. All of the Messier list is visible in a 6" with good optics. Details within Jupiter's bands becomes visible. Herschel's Garnet Star is visible as a deep orange-red. A 6" scope can keep a dedicated observer busy with new objects for a few years, and a casual observer busy for life. A 6" scope is also many amateur's favorite second scope, once they get a bigger one.

8" (200mm) Telescope
Galaxies that were visible as shapes in the 6" begin to take on detail. Arms appear, and some faint detail of objects inside the galaxies. Fainter nebulae can be explored, and nebulae visible with smaller instruments take on significantly more detail and greater extent, since the dimmer parts are now visible. Much detail can be seen in Jupiter's bands. Details of star clusters can be seen even under marginal sky conditions. Herschel's Garnet Star is a deep orange. A dedicated observer can stay busy seeing new objects for many years with an 8" scope.

10" (250mm) Telescope
Galaxies that started to show detail in an 8" telescope now show that detail clearly. It's easier to pick out nebulas that were faint in the 8". The planets start to get "too bright", requiring an aperture mask to cut down the light to bring back some detail. Herschel's garnet star starts looking amber. Details like globular clusters and bright nebulas in the Andromeda galaxy become visible. Other galaxies, like the Whirlpool and Triangulum show their arms nicely under good skies. A 10" scope can provide a lifetime of new objects to view to even the dedicated observer.

12" (300mm) Telescope
You can spend all night looking at things in the Andromeda galaxy with a 12" or larger telescope. Many galaxies show details like arms and dark lanes. You can see more detail in tight star clusters. More is visible under marginal sky conditions. Scopes that are 12" and larger provide a lifetime of use, but are best in situations that don't require a lot of moving of the scope. Some are quite portable, but they still tend to be heavy and take up enough room that many astronomers with larger scopes have a smaller scope on hand for when the big one is more than they feel like handling.

Books
There are some great books that cover thousands of objects in the sky, and how they look with different types and sizes of instruments. It's really nice to have these as a reference, so that you don't get all excited about seeing an object that's not suited for your scope, or pass up an object that you think wouldn't look good in your scope. Here are the books I recommend:

Want to Test Drive a Telescope? Go to a Star Party!

2008-07-05T11:20:00.000-07:00

A star party is an event where astronomers get together with their telescopes. Sometimes they are public events, where the astronomers are showing the sky off to anyone who comes by. At other times they are private events, either held for an organization to show off the sky to that organization's members, or it may be an "astronomers only" event.

Chances are that somewhere in your area there are star parties going on. The hard part is finding them. If there's a local astronomer's group you can start by contacting them. If not, find a local science center or museum. Local nature groups are a good place to ask as well. Most public star parties get some form of publicity. You can also ask at a shop that stocks telescopes, they probably have astronomers among their clientele.

Sometimes local events will have someone there. We will be out at our town's 4th of July celebration today (our town has a tradition of doing its 4th of July celebration a day or two away from the actual day. We're near other towns that have celebrations on the actual 4th, so we "extend" the celebration by having a fair and fireworks either just before or just after.)

You might also find that there are individuals who take their telescopes out for impromptu star parties. We enjoy just taking our telescopes along when we go places, then set up on a sidewalk somewhere and start accosting passers-by asking them if they'd like a look at whatever is in our telescope.

And then you can look on the internet, as well.

As to the private star parties, usually you can get an invite. Either an astronomer can bring you along as a guest, or if it's held for some group they may invite you as a prospective member or otherwise allow you to attend as a guest (sometimes there's a fee, particularly if food and drinks are being served as part of the event.)

Once you get to a star party, you've got access to a number of telescopes, and their users. It's not hard to get most astronomers to talk about their equipment. In some cases, they'll be busy with something, but usually the hard part will be getting them to stop talking!

Finding Things to See

2008-07-04T15:15:00.000-07:00

I was at a star party one night, and the guy parked next to me had his wife with him, and a brand new telescope. He commented that he'd put out a lot to get the scope, and his wife was skeptical of the value of the money he'd spent. His telescope was a beautiful thing, a very nice size and well designed.

When it got dark, I could hear him struggling. It sounded like something was wrong with his guidance computer, or he had run into some snag with getting it started. It was obvious his wife was getting a bit impatient. My wife was busy looking at Saturn through my telescope, so I walked over and offered to give him a hand.

It turned out he hadn't charged the power pack for his telescope's computer and drive system. He hadn't realized he needed to charge it before using it, or had forgotten. He was about to pack it in, but I offered to point his scope at a few things for him. The fact is, I wanted to get a look through it. As I mentioned, it was a beautiful scope and except for the computer I was a bit envious.

He gave me the go-ahead, so I used the manual controls to put it on Saturn. Then I stood back and let him and his wife have a look. Saturn was crisp and clear, the rings were so sharp you could cut yourself on them. Saturn's moon Titan, and two others, probably Rhea and Iapetus, were on each side of the planet.

After everyone had gotten a good look, I moved on to a series of other showpiece objects in the sky--the Double Cluster, the Ring nebula, and so on. About 1am they were getting tired and decided to pack it in. His wife was in a really good mood, though. As they were packing up, I heard her tell him "That really is a nice telescope. I hope you can get the computer working so we can see that stuff all the time!"

The biggest hurdle to beginning telescope users is getting something interesting to see in the telescope. To do this, you need to know where to point a scope, you need to get it to point there, and it has to stay where you put it.

Where to Point the Telescope

Finding the Moon is easy. Finding bright stars isn't tough (and some of those bright stars may be planets!) Finding other things takes an extra step, but doesn't have to be tough.

Get a book that gently and easily teaches you to find your way around the sky. I highly recommend 365 Starry Nights by Chet Raymo. There are other good books, too, I'll post some reviews later.

Even if you've got a computer on your scope, you'll need to know a few of the bright stars by name. There are different ones up in different seasons. You'll also want to learn at least a few of the easy constellations.

You already have a head start on this. You can probably already find Orion and at least one other constellation (like the Big Dipper if you're in the northern hemisphere--close enough for Ursa Major.) Picking up one or two more will be easy.

Pointing the Telescope

You need a finder that works. Those silly things that look like little telescopes on the side of your telescope don't work. You need a "reflex sight." This is a finder that doesn't magnify the sky, it shows a red dot or red rings on the sky. You look through it and move the scope until the red dot or center ring is on what you want to look at (or use to line up your computer.)

I recommend the Telrad. In my experience it's the best. There are some other good reflex sights out there, too. But get rid of that little telescope finder. Give it to a kid for a toy or something. Some telescopes come with a reflex sight now instead of the little finder scope. This is a plus, if nothing else it shows that the maker of the scope cares about people being able to actually use it.

The Telescope Stays Where You Put It

A mount has two jobs. Hold the scope up where you can look through it, and keep the telescope pointed at what you put it on. No matter how good your telescope is, if the mount doesn't do its jobs the telescope is useless. A so-so telescope on a good mount is worth far, far more than an excellent telescope on a bad or so-so mount.

I like Dobsonian telescopes for beginners. They are stable, easy to use, easy to set up, and they handle a lot of abuse and still work great. The telescopes I throw in my car week after week are Dobsonians.

But, Dobsonians don't have a computer to put them on things in the sky. They don't have a clock drive to keep them pointed at something as the Earth turns.

In spite of that my preference still comes down on the side of the Dobsonian. But a well-made telescope with a computer can work well, too. So long as it has a good mount.

A good mount doesn't let the telescope slowly slide down after you put it on something. It doesn't move the telescope when you lock it into position. It doesn't wobble. You can give the telescope a sharp rap and it will still show the object.

If you're trying a telescope out in a showroom, try to point it at something small and as far away as you can see (don't look toward the Sun, if it's visible!) Even if it's too close for the telescope to focus on it (like a book on the far wall of the store) you should be able to point the scope at it and lock the mount (if it's one that locks--most Dobsonians don't lock, and don't need to) and be able to see your object. It should stay there when you're not touching the scope. It should still be in if you tap the scope, either on top or the side.

High Magnification: Forget it!

2008-07-04T13:53:00.000-07:00

One of the things that lots of people worry about when buying a telescope is how high of magnification it will provide. Don't do this!

The magnifications you want are from 50x to 150x (50 power to 150 powers.) That's all. A beginner will do 90% of their observing at around 50x, and the other 10% at 150x or less. And they'll see a lot. As an experienced observer, I still spend nearly all my observing time in this magnification range.

High Magnification is Bad

High magnification is bad for a lot of reasons. I only use it when it's necessary, then switch back to low magnification as soon as I can. Here are some reasons why magnifications over 200x are bad:

It's harder to get what you want to see in the telescope.
Things in the telescope leave its field of view easier.
It's a lot harder to get a good focus.
Any stray light problems get worse (glare, nearby lights, etc.)
Any instability in the telescope gets magnified, too!

For most beginner scopes, you're going to want two eyepieces. One should give you a magnification of about 40-60x, the other should give a magnification of about 100-150x. My two favorite eyepieces give magnifications of about 50x and 120x with my two main telescopes. (Magnification is determined by both the telescope and the eyepiece--more later.)

For most scopes, this means you'll want eyepieces of about 25mm focal length, and about 15mm focal length. A 25mm eyepiece with a 2x Barlow lens can work well, too (a 2x Barlow lens doubles the magnification of the eyepiece.)

Budget to Buy a Telescope

2008-07-04T13:19:00.000-07:00

It's a circular discussion I've heard many times:

"I want to buy a telescope. How much should I spend?"

"How much do you want to spend?"

"I don't know. How much should I expect to spend?"

"What do you want for a telescope?"

"I don't know!"

"How much do you want to spend?"

"I don't know, how much should I expect to spend?"

'Round and 'round it goes...

If you're buying the telescope as a gift, you've probably already got an idea of how much you'd like to spend. In this case, you're probably concerned about how much quality you can get for your money, and how valuable a gift a telescope will be versus other gifts you can get for the same amount of money.

Whether you're buying for yourself or as a gift, here are some points to keep in mind:

The telescope will almost certainly require accessories to be easily usable.
Don't expect the first telescope to be the be-all and end-all of telescopes.
A telescope that is easy to use is more important than optical performance for beginners.
The telescope needs to be stored.
The telescope needs to be transportable, either carried to the back yard or fit in the car.
Even if the telescope has a computer built in, the user will need to learn their way around the sky.

This means you're going to want to buy more than a telescope. It's not unusual for the telescope itself to only be about half to two thirds of the total cost. Here are some accessories that you may need:

An extra eyepiece. Many telescopes only come with one eyepiece, you'll probably want one more.

A finder. Most telescopes come with a useless "baby telescope" finder. I highly recommend getting a Telrad finder, or a comparable "reflex sight" finder (more on this later.) I feel the Telrad is by far the best, however.

A carrying case, or some other way to protect the telescope during storage and transport. If the telescope is only going to go from a quiet corner in the house to the backyard, you probably won't need one. Also, some types of telescope are robust enough to transport with some simple breakdown (like a Dobsonian telescope) so these won't need a carrying case.

Star finder charts.

A red flashlight or penlight for reading the star charts in the dark.

A basic book on finding your way around the sky. I recommend Chet Raymo's book, 365 Starry Nights:
365 Starry Nights: An Introduction to Astronomy for Every Night of the Year (Phalarope Books)

You will also want an accessory box of some sort to carry extra eyepieces and such.

Don't be overwhelmed. You have lots of choices to make, and I'll be discussing all of them. But it's important to not spend the entire budget on the telescope itself, then end up with it gathering dust because a couple of simple add-ons are missing.

Technorati Profile

First Telescope Buy Guide

2008-07-04T13:10:00.000-07:00

Welcome to my guide for people making their first telescope buy! Buying a first telescope can be confusing and difficult. I have over 40 years of experience with telescopes, both as a buying customer and as a maker and designer of telescopes.

I will be discussing both the purchase and the use of scopes. I'll try to keep all my discussions in plain english, as well as giving an introduction into some of the lingo you'll want to know when you buy a telescope.

I'll cover buying a telescope for yourself, or as a gift for someone else.