Learning to use your first telescope

The internet is bursting at the seams with telescope reviews, which is why I try not to add to that. However, it is harder to find some comprehensive advice regarding what to do when you get that package in the mail, put it together, wait two weeks for the sky to clear (the "curse" of buying a new telescope), and are ready to start observing.

Learning the telescope

Of course you will be eager to start observing, but before you put your new telescope outside under the stars, make sure you read the instructions, whether included with the telescope or found online. Put it together properly and understand what each part does. If you don't, you might end up frustrated that you can't find anything or wondering why everything just looks like a blob.

DO NOT start tweaking collimation, if your telescope allows it, until you know what you are doing. I can't count how many times beginners go online saying they can't see things well in their telescope and because they've heard about collimation they immediately think that's the problem and hopelessly screw up the telescope's alignment. Most telescopes are reasonably well collimated out of the factory and won't be out of alignment so bad that it will even be noticeable to a beginner. They also tend to hold collimation extremely well, so while it's something you will need to learn to do eventually, it's not something I recommend a beginner start messing with. That's a rabbit hole you don't need to go down when you are starting out.

Tripod and/or mount

Steady views are good. Most inexpensive telescopes that beginners buy, except for Dobsonians, tend to be undermounted, giving shaky and frustrating views. That's why advanced amateurs, especially imagers, spend gobs of money on big heavy mounts and tripods. The tripod is the three legged stand that holds the mount, which holds the telescope optical tube assembly (OTA). The mount provides movement in two axes, either in altitude and azimuth or right ascension and declination. Either system allows you to point the telescope tube anywhere in the sky.

Hopefully your telescope's mount is reasonably sturdy. If not, it's not the end of the world. You simply wait a few seconds after touching it (moving the tube to an object, focusing, etc.) for the vibrations to die down. If it's windy and you have a shaky mount, try to get behind a car or the side of a building to minimize the effect. Or just wait until it's not so windy. 

Left: The Explore Scientific FirstLight 102mm refractor, with main parts labeled.

A far greater impediment to observing is if the mount is difficult to move smoothly. This is where Dobsonians shine. You simply push the tube where you want it to go. I recommend putting one hand up on the lip of the aperture and the other near the back of the tube. This gives you more precise control and leverage.

Right: A Dobsonian reflector, such as the Apertura AD8, is a simple design that maximizes aperture and stability per dollar spent.

For tripod-mounted scopes, a lower quality mount will really become an issue when you try to move the scope to center an object and track it manually. Some just aren't designed well or are cheaply manufactured, making these operations incredibly frustrating. This is why I like slow motion controls. These are semi-flexible cables with a knob on the end that you turn to allow you to move the scope in finer increments than by just pushing the tube around. 

Main optics

Telescopes work by collecting as much light as possible using a larger aperture than the pupil of your eye. Refractors do this using a set of lenses. Reflectors use a large parabolic-shaped mirror. Catadioptrics (Schmidt-Cassegrains, Maksutov-Cassegrains, for example) use a combination of lenses and mirrors to create a light path that folds back upon itself. The larger the aperture, the more light the telescope collects. 

By concentrating and focusing this larger amount of collected light into a spot roughly the size of your pupil, a telescope allows you to see dimmer objects and more detail in even bright objects like the Moon or Jupiter. You look through an eyepiece inserted into the telescope where the light comes to focus. The eyepiece contains multiple lenses to magnify the image. In short, the telescope collects and concentrates the light, the eyepiece magnifies it.

Redirecting the light path for comfortable viewing

If you have a refractor or catadioptric ("cat") telescope (like a Schmidt-Cassegrain or a Maksutov-Cassegrain), you will first insert a diagonal, usually containing a mirror tilted at 90 degrees, and insert the eyepiece into that. The diagonal ensures that you have a comfortable position for viewing high up in the sky. If your scope comes with a 90 and and 45 degree diagonal, use the 90 for astronomy and the 45 for terrestrial viewing.

Because the diagonal is usually held in by a couple of thumb screws, you can rotate it to position it more comfortably for viewing. This will change the orientation of the view in the eyepiece, like tilting your head, but you learn to know which way is which after a while. There's no law saying you have to have it set vertically and look straight down into the eyepiece.

A reflector has a diagonal of sorts, too, but it's built into the upper part of the telescope tube. It's called the secondary mirror, and like the mirror diagonal, it's a flat mirror that redirects the focused light path 90 degrees so you can view in a comfortable position, either on the left or right side of the front of the tube.

Generally, a refractor or catadioptric will mirror-reverse the view. A Newtonian reflector will simply rotate it 180 degrees. Understanding directions in your eyepiece will help you make sense out of what you are seeing compared to a chart or image.

Changing magnification

Eyepieces, what some people call "lenses" (or "oculars" for the more esoteric term), are how you change magnification, or power. Except for specific eyepieces with a rotating barrel that actually are zoom lenses, each eyepiece will give you a fixed power depending on its focal length and that of the telescope. You change magnification by changing eyepieces. 

The standard eyepiece barrel diameter is 1.25". However, many telescopes have 2" focusers, allowing for larger eyepieces with 2" barrel diameters. Most of these come with a 1.25" adapter so you can use both, or you can buy one.

Magnification (or power) = telescope focal length / eyepiece focal length. So a 750mm focal length telescope with a commonly included 25mm eyepiece will give you 30 power (30x)—magnifying 30 times what your unaided eye sees. Place the eyepiece in the focuser or diagonal, making sure it's seated all the way in, and use the thumbscrews to clamp it tightly so it won't fall out. It doesn't matter how it's rotated. 

It's best to remove an eyepiece before you move the telescope to prevent it from falling out if the thumbscrews aren't tight. Get in the habit of frequently checking the tightness of all thumbscrews for eyepieces, diagonals, and finderscopes. After 30+ years with no incident, I recently had an 8x50 finderscope fall from the upright tube of my 10-inch Dobsonian onto the cement floor of the garage. Surprisingly, no damage, but it does happen. (Most finderscopes have a tab on one side of the base of the bracket, however the ones I've seen are always toward the back, where they don't help to prevent the finderscope from sliding out on a reflector, as mine did. Makes more sense to me to have the tab in the front, but it's a refractor thing.)

Taking a seat

Although I stood the first dozen or so years when observing with a telescope, I highly recommend finding a good seat and sitting while you observe. You will be more comfortable, you will get a steadier view, and you won't tire so quickly.

The longer the tube of your telescope, the more variation there will be in the height of the eyepiece as you view objects around the sky. You can get by with a stool or chair for a shorter tube, and for telescopes that use a diagonal you can rotate it to make up some of the difference, but longer tubes such as larger Dobsonians will require an adjustable chair. 

You can decide later if you want to spend the money on a commercially available observing chair, such as the Starbound, Vestil, Catsperch, or build your own. Some people also buy and use drum thrones with varying degrees of success. 

I built my own Denver Observing Chair, a popular option, for my 10-inch Dobsonian but I often use a collapsible stool for my 6-inch tabletop Dobsonian and 102mm Maksutov-Cassegrain.

Right: My homemade Denver Observing Chair that has served me well for over 20 years.

Finding objects

Your telescope should have some sort of finderscope, either what amounts to a tiny refractor mounted on the main scope that magnifies the view or a red dot or red circle finder that projects a dot or circle on a tilted glass or plastic surface and makes it look like the dot is projected onto the sky with no magnification. In either case, it is absolutely critical that you align the finder with the telescope. The finder has a low power (in the case of a red dot, 1x) and wide field so it's easier to find objects than looking directly in the main telescope.

Before searching for anything, focus your finderscope if you have one. This is usually done by loosening a ring near the objective lens and screwing the lens housing in or out, then retightening the ring. Also put your lowest power/widest field eyepiece in the telescope's main focuser and focus on any random stars. Focusing tips are covered later in this article.

Above: Simulated view of the field for the Owl Nebula, M97, in an 8x50 straight-through finderscope on a Dobsonian telescope in a light polluted sky. The view will be rotated 180 degrees from the naked eye view, which matches the view in the eyepiece.

Left: Screenshot from Sky Safari Pro showing the 8x50 field of view, rotated to roughly match the finderscope view above. You can customize the field of view to match your own equipment, which helps to match what the chart is showing to what you are seeing in the finderscope and eyepiece. The small circle around the planetary nebula symbol is the eyepiece filed of view. You can see how much more difficult it is to find something in the eyepiece without first centering it in the finderscope.

Sometimes the labels and other clutter can obscure some of the stars, so be careful. Zoom the screen in and out to see what might be hidden.

Below: Simulated view of the same field for the Owl Nebula, M97, in a red dot finder, also in a light polluted sky. The brightest star in both views is Merak, or Beta Ursae Majoris, magnitude 2.3. The view is the same as your naked eye view, with fewer stars visible than in a magnifying finderscope. 

In neither finder will M97 be visible, so you need to aim based on the location in relation to the star patterns from a star chart and what you can see in the sky. Without the magnification of a finderscope, the red dot loses a lot of precision, so it's critical that you use the lowest power/widest field eyepiece that you have once you are pointed in the right general direction. 

Sometimes, especially if the object is very dim and you may not recognize it right away, it's better to start by pointing the red dot at the nearest bright star, Merak in this case, then switching to the eyepiece and starhopping your way to the object by comparing the star patterns in your eyepiece to those on the chart. This sounds simple, but it's often difficult to be sure exactly where you are pointing, and it's easy to get lost along the way. It still happens to me all the time. It takes practice and, even with experience, patience.

It's easiest to do the finder rough alignment in the daytime. Find a distant fixed object, like the top of a telephone pole. Put your lowest power eyepiece in (the one with the highest mm number) and center the object in the telescope. Then, without moving where the scope is pointing, look in the finder and use the little thumbscrews on the side of it to put the same object in the center or crosshairs. Do this a couple of times, even using a higher power eyepiece for more accuracy, until you are sure they match.

Each time you go out observing, check the finder alignment on a bright object like the Moon, Jupiter, or a bright star, something you'll be certain you are pointed at. First in the main telescope, then in the finder and adjust the finder as needed.  Then when you use the finder to locate an object, it will show up in the main telescope eyepiece. Depending on how accurate the alignment is and how well you positioned the object in the finder, you may need to look around in the main telescope eyepiece a little to find it. Use low power when searching. You can always switch to higher power later.

Some telescopes have a go-to computerized mount, which requires battery power and must be leveled and aligned prior to observing. These aren't as foolproof and simple as they sound, and they often don't work right. They will have tracking, though, which keeps an object more or less centered in the eyepiece. These usually come with a hand controller or are controlled via an app. 

Another computerized navigation system is a variation of a push-to configuration, where an app guides you with arrows to manually push the telescope to the location of an object. Again, this must be aligned or calibrated. The Celestron StarSense app is a good example. It takes pictures of the sky and matches them to an internal database. A freeware push-to app is AstroHopper, which requires frequent recalibration but otherwise is a good alternative to pure starhopping or expensive commercial push-to systems.

Focusing

The basic rule for focusing is to slowly turn the focusing knob, or the focuser itself in the case of the helical focuser found on many tabletop telescopes, until the object gets as small and sharp as it can be. If it does so, but then gets larger and fuzzier as you keep turning the knob, then you know where the point of focus was and that you have passed it. Just go back slowly and find it. You may have to tweak the focus in very small increments back and forth until you get the best focus possible for the seeing conditions. Usually you will have to let the scope vibrations settle after each tweak. This is normal unless you have an exceptionally sturdy mount. If your telescope has a dual-speed focuser, you can use the smaller knob for fine focus adjustment, much the same for focusing as slow motion controls on a mount are for centering and tracking objects with more precision.

Stars should look like points in low power. However, in high power, you may begin to see the "Airy disk," which is the tiny disk of light that the star is spread out into due to the optics in your telescope, its size dependent upon the aperture of your telescope. Dimmer stars will still look like points in high power, but the brighter ones should look like tiny disks surrounded by a thin circle or two, called diffraction rings. This is what you want in a well focused and collimated telescope.

Above: If you look closely, the Airy disks and diffraction rings of the two brightest stars are visible in this simulated high power telescope view. Too often Airy disk images are blown way up in scale so you don't know what you should be seeing.

What if things don't look sharp?

Assuming thin clouds aren't obstructing your view and your focus is the best it can be, then by far and away the likeliest culprit is atmospheric turbulence, or what astronomers call "poor seeing." This is what causes bright stars to "twinkle." The seeing changes based on your location, night to night, and even minute to minute. Some places in the world frequently have very good to excellent seeing, or steadiness. Examples in the United States include much of the western U.S., as well as Florida. The northern, eastern, and midwestern U.S. are often under the jet stream, meaning nights of very good or excellent seeing are rare. 

Below: Jupiter and its Galilean moons in good seeing (L) and bad seeing (R). (Jupiter images by TheWitscher via Flickr, CC By 2.0, modified to simulate seeing conditions in eyepiece.)

You'll get used to knowing what's good and bad seeing through experience. When Jupiter, Saturn, or the Moon look like they are sitting in the bottom of a clear flowing stream, you have very poor seeing. Stars will look like undulating blobs. The view will shimmer and boil as waves of thermals pass in the atmosphere. You may not be able to make out a bright star's sharp Airy disk or diffraction ring in high power. Every object will just be a moving mess. 

Don't give up just because the seeing isn't great. It's not uncommon to have very brief moments when the air steadies out despite bad seeing. It might only be a split second every few seconds, but you can see a lot in those short bursts of good seeing.

Extended objects like galaxies and nebulae are less obviously affected by seeing, so if you have a very clear night but poor seeing (a common combination), go for those types of objects. 

At the other extreme, excellent seeing means you see stars as steady points or Airy disks, bright planets seem to be much larger than you remember and show a lot more detail to an experienced eye. You can see tiny craterlets on the Moon, the shadows are sharply defined with no double-edges, and you see little or no shimmering.

Seeing is also affected by thermal currents within the tubes of some telescopes, mainly reflectors and catadioptrics. Refractors not so much, if at all. This is why you will see some Dobsonian owners with fans installed to blow air through the tube, or "cat" owners who wrap their tubes in Reflectix or other insulating material. It's all to make sure the scope design is not contributing to poor seeing. In the former case, they are trying to cool the mirror down to ambient temperature or remove thermal layers inside the tube. In the latter, they are trying to slow down and distribute the cooling so there are no big temperature differentials or plumes inside the tube to cause poor seeing. 

In most cases. setting a reflector or "cat" outside for an hour or so before observing will help, but it's not always possible, given your situation. Just be aware that it may take time for the scope to "settle."

What about collimation?

Rarely is it the case where collimation, the alignment of the telescope's main optics, is so bad that it spoils the view as much as bad seeing. There are tools you can use to check and adjust collimation, but you're better off leaving those alone until you can recognize what is bad seeing versus bad collimation. With bad collimation, you'll often see one side of an object always fuzzier than the other. Stars may look asymmetric, like little bumblebees. On nights of excellent seeing you will still have a "soft" view that you can't quite focus. But don't assume it's bad collimation until you've ruled out bad seeing, poorly made optics, or even the nature of the type of optics. 

For example, a "fast" reflector with a small focal ratio, for example f/5, will normally show "coma" at the outer edges of the field, an abberation that makes stars near the edge look like comets. Same with achromat refractors and "chromatic abberation," where you may see blue or yellow color fringing along the edges of bright objects at higher powers, an indication that the focus is going to be a bit soft. These abberations are inherent in the design. Because most everything in life is a compromise.

Learning the sky

Using a telescope is like driving a car. You can learn to drive it, but if you don't know where to go or how to get there it won't do you much good. Even if you have a go-to telescope, the equivalent of an autonomous-driving car, knowing what you want to see, when is a good time to see it, and knowing what to look for are important for enjoying your observing.

Many experienced amateurs recommend buying a book to start learning. That's fine if you are a book-learner, but with so much information available on the internet, with options to ask questions and interact with other people, I wonder if starter books aren't a little obsolete. With younger people especially, I don't think learning from a book is a very appealing process. I think it just depends on the individual.

I did start with some books, but most of my actual learning came from simply getting out and observing, and then reading about the objects I saw. Back then, the charts in the book were most important for me, but with charting apps that's changed. Unlike paper charts, apps are flexible, can be zoomed in and out and filtered and manipulated however you want. So many nights I wished my paper charts went deeper than what they showed. And don't get me started on trying to find the right chart late at night for the area I wanted to observe!

Start with things that are easy to find: the Moon, the bright planets, M42, the Orion Nebula (winter), or M8, the Lagoon Nebula (summer), and brighter star clusters. 

We measure the brightness of celestial objects primarily by "magnitude," with higher numbers meaning dimmer, and lower numbers, including negative numbers, meaning brighter. The magnitude scale is reverse logarithmic, therefore a difference of five magnitudes is 100 times brighter or dimmer and each difference of 1 magnitude is about 2.5 times brigher or dimmer. 

Venus varies from magnitude -3 to almost -5. The bright star Vega is a reference at magnitude 0.0. The limiting magnitude of the unaided eye (dimmest you can see) in a transparent, dark sky is around magnitude 6 or 7. A typical 3-inch (80mm) telescope can reveal stars to about magnitude 12. A 6-inch (150mm) to about 13.5 magnitude. An 8-inch (200mm) to about magnitude 14. This doesn't sound like much of a difference, but it makes a big difference in what you can see when so many stars and deep sky objects are at these threshold levels for seeing details, or just seeing them at all.

Extended objects like larger nebulas and some more diffuse galaxies will appear dimmer than their listed magnitudes might indicate, in which case we say they have "low surface brightness." This is one of the reasons a larger aperture that collects more light can show many deep sky objects better than smaller ones. 

Once you are familiar with using the telescope and have seen some of the brightest objects, observing the rest of the Messier Objects is a good next step. Some of them are more challenging than those in the much larger NGC catalog, but the rest are some of the biggest and brightest. Be realistic in what you try to observe, but once you gain experience, don't be afraid to try for something normally just out of reach if you have a great sky. That's part of the fun of observing!

Navigating the sky

Learn how to navigate with your telescope, depending on what assistive equipment it has. Regardless, learn how to starhop. This means comparing the patterns of the stars you see in your finder or eyepiece with those on a chart and moving the scope to the object you want to see. Unless your go-to or push-to system is really precise and functions flawlessly every time (ha!), you will still need to recognize star patterns and be able to hop to the object from where your navigation system takes you. Knowing how to starhop will also ensure you can continue observing even if your electronic system fails or runs out of power—not an uncommon occurrence.

Observing

Don't expect deep sky objects to look anything like the images you see online or in books. Your eyes, even with the help of a telescope, can't gather as much light or see most of the wavelengths represented in images. So most objects will be white or gray and look rather like dim fuzzy blobs or patches, if you can glimpse them at all. Star clusters on the other hand, at least the ones your telescope can resolve into individual stars, will look like sprinklings of beautiful points. 

Once you learn how to observe and spend 10 minutes or more viewing an object, very subtle detail will eventually start to reveal itself on clear and steady nights. Learn to appreciate what you are looking as much as how it looks.

Except when viewing the Moon or bright planets, let your eyes get accustomed to the dark, which takes about 20-30 minutes for full dark adaptation. Use a dim red light when you need light.

As you observe more, you will learn what different objects look like, what to expect, what to look for, and how to improve your observing skills. Astronomerica has articles on using averted vision, understanding distances and directions in the sky, observing the Moon, observing the brighter planets, and observing galaxies, to name a few. The internet has a huge amount of resources.

Modifying and tweaking

Even a high end telescope may require some modification and tweaking by the user, if only to customize it to your own satisfaction. Inexpensive telescopes will almost always require some modifications to get the most out of the equipment, so expect that and don't be afraid to experiment. 

Right: I added the right angle bracket and 6x30 finder to my 6-inch tabletop telescope. I also added the light-blocking craft foam, a hose clamp and extra long focuser thumbscrews to improve the helical focuser. These are all reversible mods.

However, don't start making changes until 1) you're sure you are going to keep the telescope, to avoid return or warranty issues, and 2) you've tried it as is and determined there is a modification that you can do yourself that will likely make it better. Mods for specific telescopes are abundantly available online, often offering multiple options to solve common problems. The safest mods are those that can be undone to return the scope to its original condition.

Don't rush to upgrade

Once you're comfortable with all of the above, then you can think about upgrading. Or not. You really don't need a lot of gear to see a lot. You mostly need clear dark skies, good seeing, time, patience, enthusiasm, and experience. You can't buy that. 

Unless you are missing a critical piece of gear or it just doesn't work, upgrading equipment should be the last thing on your list. You might find yourself buying a lot of stuff you don't need, won't use, or will have to rebuy once you determine what items you really want or need after observing for a while.

The important thing is to get out under the stars.

Downsizing again: The Sky-Watcher 102mm Mak

I'm not one who tends to buy a lot of telescopes. I started in 1991 with a 4.5 inch Tasco 11TR reflector on a German equatorial mount and a tripod. I used that regularly for 13 years, so if you think you'll outgrow a small telescope quickly, think again.

Then I decided to go for a Dobsonian because the 4.5 inch's tripod had literally fallen apart from use. I built a Dobsonian mount for the tube and it worked great. But I wanted more aperture, so I went as big as I could comfortably go, physically and financially, and got a 10 inch GSO Dob. I used that regularly for 20 years. 

Nine months ago, as a result of declining health, I could no longer manage the 10 inch. I separated the base into two parts that could be easily reassembled with four knobs, and I devised a simple rope harness to go around my shoulders to help carry the tube, but that wasn't enough. Very reluctantly I realized it was time to start downsizing. 

I chose the Sky-Watcher Virtuoso GTi 150P 150mm (6 inch) f/5 tabletop scope with a go-to/tracking base. I figured the tracking might help soften the blow of the loss of 4 inches of aperture. It helped a little, and I've gotten used to it, but the views in the 10 inch are just so much better. You do what you have to do.

As my health continues to decline, I can sometimes no longer even set up the 6 inch comfortably, so I decided I would need to downsize again, this time to a true "grab and go" telescope. My requirements were:

• 15 lbs. max total weight
• Carryable out the door in one piece (it's okay to come back for the observing stool)
• Good on the Moon, bright planets, and double stars because I would be using this from my light polluted home, reserving the 6 inch for any dark sky forays
• No cool down required

I settled on a Sky-Watcher Skymax 102mm (4 inch) Maksutov-Cassegrain. This scope, made by Synta, is an F/12.7, with a 1300mm focal length. The optical tube assembly (OTA) weighs less than five pounds.

This means my Svbony SV135 6-element 7-21mm zoom is all I need, giving me 62-186x in a single eyepiece, with exit pupils (aperture in mm / magnification or eyepiece focal length in mm / telescope focal ratio) of 1.6 to 0.5, good for seeing detail in bright objects.

Now I have the smallest telescope I've ever had (not counting the little Svbony dedicated solar scope), but...and this is the key...I can use it! 

I mounted it on the Svbony SV225 alt-az mount that I used on my trip to Arizona in 2024. I had bought this as an alternative to the go-to/tracking mount that came with the 150P. I can mount the 102 on the Virtuoso mount if I want tracking. In fact, Sky-Watcher sells a Virtuoso package with a 127mm Mak.

I don't really like tripods, but decided a tripod was the way to go with this setup for several reasons:

• With a tripod, I can lift the telescope and bring it in and out of the house without bending over or crouching down. Those of you with bad backs, bad knees, or similar issues will relate. This makes a big difference.
• The tripod is adjustable to match the height of the very lightweight GCI PackSeat observing stool I've been using with the tabletop scope. I can easily pick up that stool with one hand under the seat. It weighs about a pound. My homemade adjustable observing chair weighs around 15 lbs.
• I can mount other small telescopes on it as long as they have a standard Vixen style dovetail to fit the SV225 dovetail clamp. That includes my 150P.

I chose the Sky-Watcher Star Adventurer tripod. It's pretty sturdy for being inexpensive and I like that it has a tray for my eyeglasses, since this is my "quick look" scope and I don't want to have to put my contact lenses in for very short sessions. To fold up the legs to get through the door and around objects more easily, I can easily take off the tray with a simple twist, then put it on again outside.

I took the Svbony SV182 6x30 right angle correct image (RACI) finderscope off my 4.5 inch and put it on the Mak in place of the red dot finder that came with it (image at left). I can't do the contortions necessary to use straight through finders anymore. I wasn't using the 4.5 inch much anyway. It uses .965 eyepieces, and although I have some decent ones from Orion, they just aren't as nice as my 1.25" eyepieces.

A 6x30 finderscope is not ideal for a light polluted sky, but good enough for quickly finding the Moon or bright planets and stars. There just aren't that many stars bright enough to be visible in a 30mm finder in bad light pollution.

The 102 is designed to be mounted on top of a mount, not side-mounted, as I would have to do with the SV225 mount. I wasn't sure it would work, but it does. I just rotate the diagonal off to the left side a little and I can use both the main eyepiece and the finder well at any altitude setting. I had to partially take apart the mount to free up the setting circles so I could adjust them as needed, but now I can find anything using them and the finderscope.

The whole setup weighs about 15 lbs. I can move it easily in and out of the house for quick looks at Jupiter, Saturn, the Moon, or maybe some double stars or brighter deep sky objects. That's all I can see from my light polluted neighborhood anyway. It is truly "grab and go."

Avoiding cool down thermals

My fourth requirement was that no cool down be required, because I wanted to be able to pop outside with it to take advantage of a break in the clouds or just a quick look. But it's a Mak, which needs cool down, right? How can that work?

A few years ago, Cassegrain users started wrapping their telescope tubes in an insulating material, usually Reflectix, which is basically bubble wrap with a reflective layer on both sides. This prevents the scope from cooling unevenly and developing internal heat plumes as a result, which ruin seeing.

The wrap will slow this cooling down and keep the remaining heat distributed more evenly thoroughout the interior of the tube as it slowly cools. This allows observing immediately without waiting for the scope to cool down. It won't fix bad seeing (rats!), but it will make sure the scope is not to blame.

I got a 16" x 5' roll of Reflectix and found that 16" is a great length for the wrap on this scope. This includes about five inches of overlap in front for an integrated dew and glare shield, with adhesive-backed black craft felt such as this lining the inside to avoid reflections. Attached to itself with adhesive-backed Velcro, the "jacket" can be removed easily. Some say it looks ugly, but I say it makes it look like I'm observing with the Hubble Space Telescope!

I've had it out a lot already, and although it appears to be very slightly out of collimation, it's not enough for me to start fiddling with it. On nights of decent seeing (about the best we get here), I can see the five brightest moons of Saturn and detail on the planet. Stars in high power are nice and sharp with crisp Airy disks. 

For example, Alpha Piscium (4.1 and 5.2 mag at 1.8" separation) splits cleanly in 7/10 seeing, although component B is right on the first diffraction ring. That's about the practical resolution limit of the scope. I'm happy. 

Above: Simulated view of Alpha Piscium in the 102mm scope at about 170x.

Note: I noticed in writing this that a lot of what I have bought lately is either branded Svbony (products manufactured in Mainland China) or Sky-Watcher (a distribution company for Synta products of Taiwan). While I'm not beholden to either of them (I buy my own stuff with my own money and don't have any brand loyalty), they seem to be among those offering some of the better quality inexpensive astronomy products lately, with the caveat that most inexpensive gear requires some tweaking or modifying to work to its fullest potential.

(Human evolution silhouettes by M. Garde after José-Manuel Benitos, Wikimedia, CC By-SA 3.0, modified with telescopes by Astronomerica)

Equipment Tip: Add a cell phone holder to your observing chair

More and more I find I like to observe with my binoculars, using my Bino Body Mount. The problem with binocular observing is it takes two hands. I like to use Sky Safari on my phone as my charting app, and I got tired of my phone sliding off of my ever-expanding belly onto the dewy grass in the dark. It's uncomfortable to constantly be reaching over for the phone on a fold up table, so I needed something else.

A cheap gooseneck cell phone holder came free with something else I bought, so I use that, but there are plenty of similar ones such as this one you can buy. I recommend a clip rather than a clamp just for ease of use in the dark, although a clamp might work better for certain chairs. I clip it onto the arm of my zero gravity chair and I have my chart right there at hand, easily using the app with one hand while the Bino Body Mount is perched on my shoulders.

I did find that, at least on my chair, I had to clip the holder behind the locking knob (some chairs have a lever) or the arm would slide past the knob when I leaned the chair back and knock the holder off the chair. Behind the knob there is no obstruction, so I can adjust the chair in any position and the holder will stay on.

Yeah, they wobble like crazy, but when you're using your phone you're holding it steady in your hand. The holder is just to keep it handy within easy reach so you know where it is.

Observing with bad vision

I've worn glasses for about forty years, and my vision has been getting progressively worse, as it usually will. It has stabilized in recent years, but now without my glasses, everything is a blur. I started out with hyperopia (farsightedness) which was joined later in life by astigmatism (irregular curvature of the cornea or lens) so, close or far, it's now all blurry. About 15 or 20 years ago I decided to try contact lenses, and now my typical observing session requires I put them in before going out. I don't wear them regularly, only while observing.

(Image by JSB Co. via Unsplash.)

Vision correction

There are nearly as many degrees and kinds of bad vision as there are observers. Most bad vision can be corrected at least to the point where observing is possible, and the telescope focuser takes care of any basic refractive errors in your vision. That's my case. While I have +6.5 and +7.0 corrective lenses that also help correct for astigmatism, the correction is not perfect. Nevertheless, for me progressive lenses correct enough for me to get through life. I don't recommend trying to use progressive lenses at the eyepiece.

Contacts don't do quite as well for me but they work better at the eyepiece. Although I have toric lenses, the astigmatism is still pretty strong, and I've gotten used to the idea that my views of astronomical objects are not going to be ideal—one of the reasons I don't spend a fortune on eyepieces! I have what's called monovision contacts. My left side focuses at about three feet to infinity and my right side focuses around reading distance. It takes some getting used to after wearing glasses, but within half an hour or even less I'm fully functional. 

(Star images rendered from AladinLite.)

Glasses on

Some people just observe with their glasses on. This requires you to have eyepieces with long eye relief, such that you can have your glasses in between your face and the eyepiece lens and still see the whole field of view, or at least most of it. 

Eye relief is the distance in millimeters from the closest your eye can get to the lens to the furthest point you can pull it back and still see the entire apparent field of view (you can see out to the circular edge of the eyepiece field). For eyepieces with very short eye relief, usually in the smaller focal lengths, this may be the same distance, and your eye has to be almost touching the lens. This can force you to strain and your eyelashes will deposit oil on the lens. 

When using glasses, this point may be closer to the eyepiece than you can actually place your eye, and in that case you will never be able to see the full field of view. Eye relief that is too long may require you to move your head around to catch the sweet spot and can be equally frustrating as the view blacks out when you move your head slightly out of position. Eye relief is also dependent upon the shape of your eye socket and your glasses.

I have yet to find an eyepiece with enough eye relief that works with my prescription, and I have progressive lenses anyway, so I don't wear my glasses when looking through the telescope. I can, however, use various binoculars with long eye relief.

Observing without glasses. Notice how close the eye can get to the lens, making longer eye relief unnecessary to be able to see the full apparent field of view of the eyepiece, which in this case is 82 degrees, nice and wide. Contact lenses require no additional eye relief.

Observing with glasses on. Compare to previous image, noting the much greater distance from the top surface of the eyepiece to the observer's eye. Long eye relief when wearing glasses is critical to being able to see most or all of the eyepiece field of view. This Astro-Tech UWA 10mm eyepiece has only 10mm of eye relief. Not long enough for eyeglass wearers, who need a minimum of about 17-20 mm.

(Images by Astronomerica.)

According to Don Pensack's 2025 Eyepiece Buyer's Guide, eyepieces currently available range in eye relief from a mere 1 to 3 mm for the Harry Siebert Optics Planesphere series to a whopping 46 mm for the Masuyama 60mm 2-inch eyepiece. The caveat on any eye relief figure is that the numbers often only count the measurement from the glass surface not including additional inset or eyecup. So if anything, the effective eye relief may be shorter than the advertised eye relief. This thread from Cloudy Nights discusses some of the better eyepieces for eyeglass wearers. Scroll to post 14 to bypass some rather less useful posts.

Glasses on and off

Another way to cope is to use your glasses when reading a chart or looking up at the sky and then taking them off each time you put your eye up to the eyepiece. This may work especially if you have a relatively mild prescription and maybe only use glasses for reading. For us hardcore Magoos (link provided for younger folks who have no idea), this is fraught with danger. 

(Superman image by DC Comics)

Let me relate my experience in that regard. Before I switched to contacts, I thought I would just swap my glasses on and off when observing. While annoying, this did work to some extent. Until one night, when I placed my glasses atop the roof of my car. They slid off with the heavy dew, and here I was with no way to search for them. Oh, I had a red light, but everything was blurry. I was afraid to move, but I took one step in the direction I thought would be away from the glasses and, you guessed it, heard and felt a sickening crunch underfoot. I managed to drive home that night using an older pair of glasses I had kept as a backup, but that was it for me, and I got contacts shortly thereafter. 

If it works for you, go for it, but be careful. Sometimes I still do use this technique (with my backup glasses!) when I'm just out for a quick look in the backyard or I'm taking a quick look in my solar scope. I recommend velcroing a soft case to your scope or table so you can slip the glasses in there, rather than trusting to a pocket that could contain who knows what that could scratch your lenses or just laying them on a table. I've tried keeping them on eyeglass retainers around my neck but the constant bumping and scraping as I leaned over the telescope was annoying and made me worry about scratches.

No glasses

You might be lucky enough to still be able to read or look at the sky without your glasses and still see reasonably well. In that case, just put your glasses away and use your uncorrected eyes. I did this until the stars just started looking like fuzzy blobs and I was straining to read charts with a magnifier in the dim red light of my flashlight. A man's got to know his limitations, and I had reached mine.

Contact lenses

For me, contacts are really the best solution. With my monovision lenses I can read reasonably well up close, I can drive, I can see the stars reasonably well when I look up, I can see pretty well with any eyepiece, and I've gotten used to using one eye for each. Another benefit is at public star parties, where I can focus an object in the telescope and know that people with reasonably good vision will get a decent look. But a tweak of the focuser will work for most people with uncorrected vision issues, other than astigmatism. I usually encourage people to take off their glasses to observe and just refocus, as long as they don't have bad astigmatism.

There are a few downsides, though. Especially if you don't wear them often, contacts can be itchy, scratchy, and blur out sometimes, especially as your eyes get tired. I sometimes struggle to get them to stay in at first, although other times they just slide right onto my eyeballs and stick. I've had them get stuck under my eyelid when I rubbed my tired eye, and I've even put two in at once, thinking the first one didn't stick and had dropped on the floor. 

Or maybe you just don't like touching your eyeball? Ewwww! (Image by Moist.acuvuehk via Wikimedia, public domain)

I always take a second pair of contacts with me in case I get a tear in one, it just feels crappy, or I somehow lose one out of my eye. Also bring eyedrops to rewet them if they get too annoying. The lens solution bottle won't help unless you want half the bottle all over your neck and down your shirt. Trust me on that one.

Televue DIOPTRX

Televue makes a device they call DIOPTRX that can help with mild astigatism. It looks like a filter with a fold-down eyecup attached that you can thread onto a variety of Televue eyepieces. I've read some accounts that all say it works well. If your astigmatism is relatively mild, but bad enough that correction would make it worth the cost, and you have Televue eyepieces, you might want to check it out.

Can I take pictures through my telescope with my phone?

The short answer: Yes, but prepare to be underwhelmed. My question to you then would be: Why? If the answer to that is you just want something to text or post to show what you were looking at, go for it, but you're really not going to impress anyone. I have people at public events always wanting to take a picture of the Moon through the scope, and I usually oblige them by taking the picture for them, but it slows the line down and won't impress anyone but total non-astronomy folks (maybe). Still, I get it. People want something besides a memory to take home. Frankly, I'm happy with the memories.

Confession: Against all logic, I sometimes try to take pictures through my telescopes with a cell phone at the eyepiece, knowing it is probably a waste of time. The only decent pictures I've ever gotten were of the Moon, which are still far below almost any image I can find on the internet and the detail I can see visually, and some pretty cool images of Spica and Arcturus with an apodizing mask on my 10-inch. Otherwise, the images suck. Granted, I am using a Pixel 6a, which isn't exactly cutting edge now, so if you have a newer phone, or the latest and greatest (for now) iPhone, then you might have better luck. 

Anyway, here is a gallery of images I took through my 10-inch and 6-inch Dobsonians with the Pixel 6a, as a baseline for what you might expect to get, depending on your phone's camera. I will say it is difficult to get the phone's camera lens lined up with the eyepiece while still being able to snap an image before the object drifts out of view. Although I have no experience with eyepiece phone adapters, the general consensus appears to be that they are fiddly and mostly a waste of time and money. If you do get one, the Celestron NexYZ is often recommended. The images I've seen from them, however, are no better than my handheld images. Phones seem to be much better at getting non-optically magnified images like the Milky Way, or a lunar eclipse over some scenery using their night vision mode, or whatever they call it. Bright comets can be kind of nice.

Left: The Moon rising over the hills. This was so cool that I wanted to take a picture to put in my log for that unique sight, just to remember it better. To me, this is the best kind of use case for taking an image through the eyepiece. 10-inch dob.

Left: The gibbous Moon, zoomed in and cropped to show the level of detail, which is nowhere near what I could see visually. 6-inch tabletop dob.

Left: Spica with the apodizing mask. Pretty psychedelic, but rather pointless. Well, there actually are a lot of points. 10-inch dob. Apodizing masks are used on larger telescopes to negate some of the effects of poor seeing for splitting double stars and seeing more planetary detail. I didn't notice any improvement on my scope, as expected, although the kaleidoscope effect is interesting.

Left: Arcturus with the apodizing mask. Far out, man! 10-inch dob.

Left: Comet C/2023 A3 (Tsuchinshan-ATLAS) through a 6x30 finder. The shot through the eyepiece was too awful even to post here as a bad example.

Left: The same comet using the phone's "night vision" capability, without magnification. Especially with distinctive scenery, this can bring back the memory of the night much better than an eyepiece shot can.

So there you have it. Casual photos? Maybe. Anything more, get a SeeStar or go down the imaging rabbit hole and be prepared to spend some money and a lot of time learning processing. If you want to do planets and the Moon, a basic planetary camera might work for you, but you have to seriously ask yourself why you are wanting to do imaging. It's not for everyone but some people just love it, and it's more forgiving of light pollution.

Astro imaging is indeed a different hobby entirely from visual observing. I remember photographing Comet Hyakutake on a homemade barn door mount with a poorly functioning stepper motor and a film SLR camera. I don't even know where the picture is now, but it was so much less inspiring than the actual view of seeing the comet from that dark sky, stretching overhead like a flashlight beam. 

After that, I decided not to waste good observing opportunities trying to capture something mediocre to take home with me, unless I spend less than a couple minutes doing so out of the apparently primal urge for a tangible keepsake of everything to post on social media.

For me, give me visual every time. I'll find the pretty pictures on the internet—and I do, for placing in my log or notes to go along with my visual descriptions, or just to see what an object can look like to an imaging chip with a lot of computer manipulation.

An inexpensive hand controller for your SynScan mount

I have a Sky-Watcher Virtuoso GTi 150P 6-inch collapsible tabletop telescope, which has become my go-to scope (pun most certainly intended) since I am no longer able to heft my 10-inch Dobsonian around on a regular basis. 

This scope uses the SynScan app to control the mount, which appears to me to be a cheaper version of the AZ-GTi mount. My particular scope's go-to works poorly, so I use the mount strictly for tracking when viewing the Moon and brighter planets from my Bortle 8-ish home. I built a more reliable alt-az tabletop mount that I use for everything else.

The SynScan app (shown at left), in my opinion, is rather poorly rendered and clunky. Beyond that, though, my main dislike is the fact that with any app controlling your mount, you have to look down at your cell phone and use the touchscreen to move the scope around. This makes it difficult to see the effects in the eyepiece and I have found it very frustrating.

To solve that problem, I did some google-fu and found that several people have used game controllers to replace at least some of the commands on the app. All I was looking for was one that would let me control the altitude and azimuth movements with actual buttons that I can feel at night without taking my eye from the eyepiece. 

I didn't want a full size game controller, and found a little mini one that someone mentioned on this Cloudy Nights thread that will indeed work for movement control with my scope. For $5 shipped from Aliexpress (you won't get that low price now), I picked up an 8BitDo Zero 2 keychain-sized mini controller. Its Bluetooth paired easily with both of my cell phones (Google Pixels). 

Now I can control the scope without taking my eye from the eyepiece. What a difference this makes for frustration-free viewing! Because the tracking on my scope is rather poor, I frequently need to recenter the object in the field of view, and this makes it much easier than using the touchscreen on the phone. Panning around on the Moon is much more pleasant. Also, my mount has a tendency every once in a while to go slewing off into the ether somewhere on its own, and this way I can quickly stop it and bring it back under control without fumbling with my cell phone. 

I use it one handed, and it works even if I have thin gloves on or hold it inside my pocket. It does have a steady blue light when connected to the phone's bluetooth, so you might need to keep it in your pocket or tape over the light if you use it around other folks in a darker environment. In my light polluted yard, it makes no difference.

While I can't comment on how well this works with other mounts and apps, for $20 (now the lowest price on Amazon), it might be worth a try. Or if you already have a game controller, try that one. It has made a big difference in the usability of my tracking mount.

How much does amateur astronomy cost?

tl;dr: It costs whatever you have to spare that you want to invest in it.

I was recently reading a thread on the Cloudy Nights amateur astronomy forum in which the poster was complaining how some people are always claiming how expensive amateur astronomy is, when it "really isn't." These threads pop up periodically, and usually follow the same course. (Above: Andrew Magill from Boulder, USA, CC BY 2.0, via Wikimedia Commons; Astroboy by Astronomerica)

First, let me comment that many of the most frequent posters on Cloudy Nights seem to mostly be retired engineers, white collar skilled workers, or successful retired "boomers" (full disclosure: I am a retired "boomer") who have fairly large disposable incomes. Often someone will state that compared to expensive motorcycles, high end photography, golf memberships and green fees, high end gaming, skiing equipment and lift fees, and the like, amateur astronomy is cheap. Well, if you look at it that way, it is. Until you buy land out in the boonies and build your own observatory to house your 6" refractor imaging rig. But most of us will never have the money, opportunity, or life situation to do that.

But how about those people, and not just kids, who don't have thousands or even hundreds of dollars to spend on a hobby? I remember when I lived in a 24' travel trailer, had a minimum wage job, and thought that buying a 4.5" Tasco 11TR department store reflector for almost $200 was a huge splurge—and it was for me. By the way, I did start out with $20 Tasco binoculars before I could afford the telescope.

I grew up being frugal and I still am as a matter of principle. Even if I can afford something more expensive, I like to see how much enjoyment I can get out of a less expensive option. That extra 300% in price often only buys a 10% improvement in what really counts: enjoyment. Maybe 1000% will buy a 50% improvement, but that often takes the expense well out of a person's budget range. (Above: At Bull Creek Wildlife Management Area in Central Florida, 1993, with myTasco 11TR department store reflector. Some of the happiest nights of observing in my whole life.)

Hence, with Astronomerica I attempt to demonstrate that it doesn't take a lot of money—whatever that means to you—to enjoy amateur astronomy. We constantly read about "hobby killer" cheap telescopes. That's probably what my 4.5" Tasco was considered by many at the time, yet it helped me develop a hobby that I have enjoyed for the rest of my life, because if you don't approach it from an elitist perspective, it's not a bad scope. 

No one wants to buy crap, but even now there are some decent telescopes for $250 or even less. I just picked up a Svbony SV510 solar telescope (above) for less than $10 new that actually shows sunspots pretty well, even if it's on a very rickety tripod. If that's what you have to start with, then go for it. Just understand the limitations. "Perfect is the enemy of good" (Voltaire).

Many times I read posts where people say for $500 a particular piece of gear is too good of a deal not to buy, even if it's just to try it out. After all, it's "only" $500! Don't we all wish we had that kind of mad money? Others consistently recommend finding a higher quality piece of gear used. But most people don't want to wait weeks, months, or even years for that particular equipment to come up on the used market, just to see it sold to a retired "boomer" engineer before they can even get home from school or work to check the classifieds.

I know from experience that there are ways to get a lot of enjoyment out of amateur astronomy for very little cost.  But as you get more into the hobby it can cost you more. Want to get away from your Bortle 9 city lights out to the country? Better have a car and gas money, or a friend who has both and is also into astronomy (good luck with that). Want to buy that perfect beginner 8-inch Dobsonian? Better have $600, plus a phone with a charting app or money for a star charting book, plus a suitable observing chair, plus good cold weather gear, etc. 

It does get expensive by many people's standards. But do we really need that 8-inch dob as our perfect starter scope that will "serve us well for a lifetime?" No. You can get good binoculars for a third of that price, and "recommended" cheap binoculars for perhaps half of that. Cheaper if you get them on sale, or the price of club dues if you're lucky enough to have a local astronomy club that has some to borrow. (Above: Apertura 8-inch Dobsonian, the "perfect" starter scope for those with $600 to spare.)

While I love forums like Cloudy Nights, Stargazer's Lounge, and Reddit (r/telescopes), there is a strong tendency for the frequent posters to make it sound like if you don't get this or that recommended equipment, then you're making a huge mistake. "Better to buy once and cry once," is the mantra. Easy to say if you have the money on hand to do so. If not, they then suggest you wait and save your money until you can. Depending on your situation, that might take many months, if not years. There really is no reason not to start with whatever modest equipment you have, even if it's a cheap lawn chair, your own eyes, and a bottle of bug spray. (Left: Nikolay Andreyev, Public domain, via Wikimedia Commons, modified for amateur astronomy FOMO)

I recommend you read those forums but don't fall into the trap of thinking you have to have a pile of high quality equipment to enjoy amateur astronomy. Consider the situations of those making the recommendations, and consider your own situation. One user may have 20 telescopes, 50 eyepieces, and a fountain of experience (who is also the one that tells you "Better to buy once and cry once!"). You don't need to be that person. You aren't that person. You can enjoy the night sky the way you can, given your own means and situation. Don't feel like you're missing out. You're seeing the same things everyone else is. Someone will always have a better view. Don't let that keep you from looking up.

Enjoy the journey, wherever you start and wherever you wind up.