Purchase Recommendations

Purchase Recommendations

On This Page

  1. Telescopes
  2. Computerized Mounts
  3. Astrophotography
  4. Eyepieces
  5. Barlow Lenses
  6. Other Accessories
  7. Eventual Upgrades

If you ask a group of amateur astronomers what recommendations they have for specific things to purchase, you are likely to get just as many responses. One’s recommendations are invariably colored by one’s own experience. But everyone’s experience is different. What’s good for one person won’t be for someone else. This is true not only where astronomy is concerned but also with anything else in life.

What follows are my own recommendations based on my own experience. Although I’ve tried to give consideration for a variety of interests, my own experience definitely colors what I advise others to have a serious look at.

Telescopes

It’s important to note again that different styles of equipment appeal to different people and different observing needs. There is no one telescope that is “the best” for all applications. The important thing to do when making a decision about what to get is to evaluate what is most important to you (aperture, performance, price, etc.) and find the gear that suits your needs best.

Generally speaking, I would avoid going below 3 inches (75mm) and above 10 inches (250mm) in aperture. Smaller scopes won’t give you the light grasp you need to have an overall satisfying observing experience, and larger scopes are simply a pain to lug around and won’t get used often. Within that range, 4 to 8 inches seems to be the sweet spot. Four-inch scopes are highly portable but lack the light grasp for that immersive experience of observing dim objects. Eight-inch instruments are far more likely give you that experience and are still small enough to be relatively easy to set up and take down. Where the perfect balance is between aperture size and managability is something you have to decide for yourself.

Perhaps one buying strategy when purchasing your first telescope is to seek out a smaller, reasonably priced, but still well-made instrument that will give you the opportunity to gain experience using a telescope and that will also continue to be useful as a complement to a possible larger-aperture scope that you may decide to get down the road. Small telescopes function well as convenient, grab-and-go instruments, but they also tend to induce a phenomenon known as aperture fever—at some point, you may find yourself craving for more aperture. If you get to that point and act on it after having first bought a quality small telescope, you can continue to use your smaller instrument when you want something for quick-look sessions while having a larger scope for those occasions when you really want to dig in and spend a number of hours observing.

Catadioptrics

Maksutov-Cassegrain telescopes offer a long focal length in a small, compact bundle. Their higher magnification also helps with spreading out urban skyglow. Those with an aperture of around 90 to 102mm offer good views of the Moon and planets, which are just as well observed from the city as they are from the country. But their small aperture will limit the number of deep sky objects that are accessible with it.

My 4-inch (102mm) f/12.7 Orion Maksutov-Cassegrain telescope is very well suited for high-magnification planetary observing all in a lightweight and very convenient package. My manually-driven, mid-sized Orion AstroView equatorial mount carries this scope with no problem. This was my very first scope I ever bought, and I have a sentimental attachment to it. It’s a small scope that is highly transportable and has really crisp optics. Its focuser is smooth, and I have little problem achieving focus even at higher magnifications. Although Orion went out of business during the summer of 2024, Sky-Watcher sells a version of this telescope. I very much recommend it.

The scope that I use for serious observing at home in the city is an 8-inch (203mm) f/10 Celestron Schmidt-Cassegrain telescope that I use on a heavier, manually-driven Orion SkyView Pro equatorial mount. This setup gives me a good amount of aperture without being obnoxiously large. In my mind, eight inches is the sweet spot for a telescope aperture. It’s big enough for engaging views of a wide variety of deep space objects but is still a very manageable size that is well suited for regular use.

Any Celestron Schmidt-Cassegrain is a decent bet. The more aperture you get, the more satisfying of a view you’ll have of dimmer objects. If you purchase an optical tube assembly (OTA) separately, remember to find an adequate mount.

Refractors

My 3.5-inch (90mm) f/11 Meade Series 390 achromatic refractor punches above its weight. This was the first refractor I ever owned, and it introduced me to the crisp, high-contrast views that refractors are known to provide. It does suffer from some chromatic aberration, but it’s not bad at all especially considering that it’s an achromat and not an apochromat. I use it on my Orion AstroView equatorial mount. Because of the force of momentum its long length exerts on the mount, I am reluctant to go any bigger on that mount. I use this scope mostly for lunar observing and, with proper filters made for this purpose, solar observing. Unfortunately, this refractor is no longer sold new, but many other possibilities for long-tube, small-aperture refractors exist on the market.

If I were seeking out a good achromatic refractor, I would look for 80 or 90mm of aperture with a generous focal ratio (f/10 or above) to keep false color under control.

Reflectors on Alt-az Mounts

For absolute rock-bottom—and I really do mean rock-bottom—I would consider the Celestron Cometron FirstScope. If you have a steady table and want something uncomplicated and complete out of the box to put into the hands of a young astronomer or to take with you on a camping trip for carefree use, this is a good choice. I once owned one of these scopes, and I bought it mainly as a project—I had it disassembled for parts within 15 minutes of it being out of the box. Out of all the variations of the FirstScope that are out there (and there are many), this version offers the best set of eyepieces. But its primary mirror is cheaply figured, its fast f/4 focal ratio is hard to get right at that focal ratio and price point, and its build quality is hit or miss. This little scope is good for getting your hands dirty with casual, low-magnification, wide-field views of the heavens. But don’t ask too much of it. Expect lots of distorted-looking stars at the edge of the field of view and a struggle to see the rings of Saturn.

For those occasions when I want a quick-grab scope or when I want to scan the sky at low power, my 4.5-inch (114mm) f/4 Zhumell Newtonian reflector telescope that I use on a home-built wooden mount fits the bill. Other branding variations of this telescope include the Celestron Cometron 114AZ. I am 99.9% certain that they all come out of the same factory in China. This scope has been around for years, and many serious amateur astronomers have one on hand for a convenient observing option. It makes for a good, inexpensive, lightweight grab-and-go scope with decent optics that give me satisfying views at low power. This is a scope that really benefits from adding a Barlow lens (discussed below) when I want more than low magnification. But it’s not really well suited to be used for anything more than casual, spur-of-the-moment observing. And other scopes perform far better for planetary observing or high-magnification work. Its cheap focuser is its weakest link. When I operate anywhere above 50 or 60x, I struggle with achieving sharp focus. The focuser has a gooey, sloppy feeling that is the result of the infamous “glue grease” that the manufacturer uses to compensate for any loose play in the movement of the focuser tube. When I’m out with it for more than an hour or so, I start to want something with better light grasp, better hardware, and/or better optics.

Reflectors on Dobsonian Mounts

Small scopes are great for the convenience they offer. But there is simply no substitute for aperture, and there’s no better way to get that aperture for the least amount of money than Dobsonian-mounted reflectors. They may not have that classic telescope look, but they really deliver at the eyepiece.

10-inch Dobsonian-mounted reflector
My 10-inch Dobsonian-mounted reflector I once owned.

For trips out to the country and darker skies, I once owned a 10-inch (254mm) f/4.7 Orion Dobsonian telescope whose prior owner had stripped its push-to navigation electronics and other more critical parts. I managed to restore the scope to functional condition using simple hardware store parts, and I didn’t mind it missing its electronics for reasons I discuss below. This scope had excellent light grasp and showed me fine detail in faint objects. But a 10-inch telescope is perhaps the largest in the class of medium-sized scopes. Anything larger than that and you’re getting into big-scope territory and all of the encumbrances that come with it. Personally speaking, a 10-inch scope is definitely the limit for me in terms of how big I would ever want to go.

GSO’s 8- and 10-inch Dobs have great optics, excellent build quality, are very well accessorized, and generally stand out as an unbelievable value. They retail under a variety of brand names such as Apertura (8-inch and 10-inch models). I got a feel for a friend’s 10-inch GSO Dobsonian reflector a few years ago, and I was very impressed by the smooth movement of the scope on its mount, its focuser, and the overall quality of the package. If I ever needed to replace the 10-inch Dob I have, I’d go for either the 8- or 10-inch models depending on what level of physical ability I had at the time.

Computerized Mounts

A debate has raged about computerized mounts since their introduction a number of decades ago. One camp argues that one is not a true astronomer without the ability to navigate the sky visually and that using a computerized mount is akin to having a bag over one’s head. The opposing group maintains that light pollution has gotten so insidious in recent decades that go-to technology is an essential addition to the hobby, one that enables the amateur astronomer to navigate the sky in spite of the increasing absence of dark skies.

I don’t have any computerized mounts. My preference is to tend towards simplicity and to put my money towards better optics rather than fussy electronics. A typical go-to system will add hundreds of dollars to the total cost of a setup—money that, in my mind, would be better spent on more aperture, better optics, quality eyepieces, or other accessories. Even in the city, I can make out at least the bright stars and, on good nights, some of the dimmer ones, too. It didn’t take me long to find that I didn’t need a computer to do the navigation for me and that the hobby was more enjoyable without one getting in the way.

Another argument against computerized mounts relates to convenience. A powered mount requires a battery, mostly likely a rechargeable one. A rechargeable battery requires charging, of course. Charging it requires you to remember to charge it, which itself requires forethought. If one night you see that it’s clear and that you’re in the mood for an observing session lasting a number of hours, what a disappointment it would be to discover that you forgot to charge the battery and thus were not able to run your mount. I’ve also seen friends arrive at a dark-sky site an hour’s drive from their home only to discover that they forgot their battery. Having to remember a power source is just one more complication for a hobby that can get pretty complicated in a hurry.

I’ve encountered countless individuals who struggle with their computerized mounts and ultimately give up on the hobby all because of a dumb computerized mount. What a shame.

Astrophotography

Beyond pointing a camera into the eyepiece and taking pictures of the Moon, I’d advise against diving into the world of astrophotography before getting meaningful experience as a visual observer. Astrophotography is a complex and very expensive sub-area in amateur astronomy that can lead to a lot of aggravation especially for beginners. Take it easy at first and enjoy the view before even thinking about capturing images of what you see in the eyepiece.

Eyepieces

I would start with whatever eyepiece(s) that came with your telescope when you bought it and maybe add one more. Take it easy at first. Don’t go overboard with buying eyepieces before you’ve had a chance to use your telescope. Eyepieces are important, but a little experience will quickly tell you what your preferences are. Spending some time working with what you have will put you in a better position to decide on additional eyepieces later on.

Pay attention to having an eyepiece set that gives you an even spread of magnifications. Roughly 30 or 40x between magnifications is a good place to start. If an 8-inch (200mm) telescope with 1200mm focal length came with a 25 and 10mm eyepiece, I’d consider adding a 14mm eyepiece. That set would give me 48x (25mm eyepiece), 86x (14mm eyepiece), and 120x (10mm eyepiece).

But if I had a small 4.5-inch telescope with 450mm focal length that came with a 17 and 8mm eyepiece, I’d live with that set for a while before thinking about getting something else. That pair of eyepieces would give me two magnifications: 26 and 56x. After a few nights with the scope, I’d assess what getting another eyepiece would do for me. Would an eyepiece that would give you more magnification be asking too much of the telescope? Would you want a better-quality eyepiece to replace the 8mm one that came with the scope? A little bit of experience will tell you right away.

As I discuss above, be careful about selecting eyepieces that give you a good range of magnifications, and don’t push magnification too high or too low.

Plossl Eyepieces

A collection of Plossl eyepieces
A collection of Plossl eyepieces.

Plossl eyepieces, which feature four lenses arranged in two pairs, work best at higher focal lengths (and lower magnifications), i.e., around 17mm and upward. I find that eye relief starts to get tight at eyepiece focal lengths of 15mm and lower. I still make regular use of my 32, 25, and 20mm Plossl eyepieces. Any GSO-built Plossl eyepiece at 15mm and longer is a good bet for additional relatively inexpensive starter eyepieces.

Starguider / Paradign Dual ED Eyepieces

Starguider Dual ED eyepieces
Starguider Dual ED eyepieces.

The Starguider Dual ED (Agena) and Paradigm Dual ED (Astronomics) eyepiece lines, each of which come out of the same factory, represent one of the best values in the hobby. They may seem expensive especially when you’re just getting started. But adding one whose focal length complements whatever other eyepieces you may have will substantially increase the satisfaction you get from observing. Their comfortable eye relief, wider field of view, and excellent edge-of-field performance make them a significant step up from Plossls of equal focal length.

Barlow Lenses

A typical 2x Barlow lens
A typical 2x Barlow lens.

The additional of a Barlow lens, which doubles the magnification of an eyepiece by whatever factor is specified for it, is a possibility. But I go back and forth on whether to recommend this from the outset.

Adding that accessory increases the magnification of an eyepiece and also increases the effective focal length and focal ratio of a telescope. Some telescopes, particularly short-tube reflectors with rather unforgivingly low focal ratios around f/4, really benefit from the addition of a Barlow lens because it stretches out the scope’s focal length and increases its focal ratio.

But in certain other instances, adding more lenses into the path of light between the front of the telescope and your eye adds more opportunities for optical aberrations and other negative side effects to work their way in. The quality of the Barlow lens has a lot to do with how well it performs, too.

Barlow lenses can also change the optical behavior of an eyepiece. Particularly with eyepieces that have longer focal lengths and longer eye relief, the Barlow lens will lengthen that eye relief even further. You may find that you have to position your eye very far away from the eye lens and that the eyepiece will exhibit blackouts much more than if you used the eyepiece by itself.

Especially when observing the planets in a telescope that already has a long focal length, I find that using a well-made eyepiece with lower focal length yields a far superior view than using a longer focal length eyepiece with a Barlow lens. After buying a few Barlow lenses during my first few years in the hobby, I’ve since moved away from using them in most of my scopes.

GSO Barlow lens attached to the end of an eyepiece to boost magnification by 1.5x
GSO Barlow lens attached to the end of an eyepiece to boost magnification by 1.5x.

GSO’s 1.25" 2x Barlow lens won’t break the bank if you feel that trying one out might benefit you. This particular Barlow lens features a lens cell that unscrews from its barrel and attaches to the end of an eyepiece. Doing this increases the magnification of an eyepiece by 1.5x. That adds a whole other dimension of flexibility to one’s calculations: you’ll get three magnifications out of any one eyepiece. But remember the thoughts I expressed above about the negative side effects that Barlow lenses can introduce.

At bottom, it all depends on your setup. Wait until you have some experience with your particular telescope before making the decision to buy a Barlow lens.

Other Accessories

A small number of other highly desirable accessories will enhance your observing experience.

Magazine Subscriptions

During my first few weeks in the hobby, I picked up copies of the current issues of both Sky and Telescope and Astronomy magazine from the newsstand at my local grocery store. I found them to be an invaluable source of information, and I quickly subscribed to both publications.

In particular, Sky and Telescope is a thoughtfully-written publication. Published since 1941 after The Sky and The Telescope merged, the magazine is somewhat of an institution within amateur astronomy.

Star Atlas

There are basic star maps in Dickinson’s NightWatch, but you’ll quickly outgrow them. When you reach this point, several other options exist for more detailed star charts.

I regularly use and highly recommend Sky and Telescope’s Pocket Sky Atlas in its regular size or jumbo size.

Red-light Flashlight

With a star atlas in hand, you’ll need a way to see and read it in the dark.

Any white-light flashlight will ruin your dark-adapted vision. Red light has the least effect, and red-light flashlights suited specifically to astronomy are readily available. There are tons of red-light flashlights out there—search the internet for “astronomy red light flashlight.”

An excellent value in a simple but effective red-light flashlight with a dimmer control is Celestron’s Night Vision Flashlight. Lots of other options exist out there. Nothing fancy is necessary.

Moon Filter

Moon filter
Moon fliter.

Since a telescope’s main job is to gather light, looking at something as big and bright as the Moon in a telescope can be like looking at a car’s headlight. Having a way to cut down on that light will make for a much more comfortable lunar observing experience especially when the Moon reaches its full phase.

GSO’s green-tinted 18% transmission moon filter and their ND 0.3 50% transmission neutral density filter are both good buys.

When I first got started in the hobby, I made regular use of variable polarizing filter like this one offered by Agena, but I’ve found lately that the dual filter creates annoying reflections of the Moon’s light off my eye. I haven’t been using it much lately.

Observing Stool

I’m amazed how much my observing experience became more satisfying when I simply had a seat. I find that it’s far easier for me to hold my body steady when I’m seated at the eyepiece rather than when I had been standing up.

At the end of the day, a stool is a stool. Anything to sit on will aid with keeping your body steady at the eyepiece. It will help you concentrate more on what you’re observing and less on holding still. Numerous options exist for height-adjustable stools made specifically for astronomy. But at least from the outset, I would suggest just using anything you may already have on hand.

Collimation Tool

If you have a reflector, you’ll need some kind of tool to collimate it. Unless your reflector arrived in perfect collimation after shipment to your home (not likely), having the means to make the necessary adjustments to get the optics lined up for a first-rate observing experience is critical. These accessories can be as simple as a dust cap with a small hole and a reflective surface on the inside or as elaborate as a device featuring a laser. A good reflector will often include a collimation tool and instructions on how to use it.

I own two collimation tools: a Celestron Collimation Eyepiece, which I like for its simplicity and the fact that I don’t need to power it with batteries in order to use it, and a GSO Deluxe Laser Collimator III, which is nice to use in situations where I don’t have a light source (for example, when I arrive at an observing site at dusk). Both tools work well.

Eventual Upgrades

At some point, you may find that you’ve outgrown the set of accessories that came with your scope or that you bought when you first got it. This may especially happen when you get a feel for what upgrades would do for you after trying out a friend’s higher-end gear on the observing field at a star party.

Finder Scopes

This is probably the first upgrade I would suggest. My first telescope came with a small 6 x 26 finder scope (i.e., 6x magnification and 26mm aperture). Under urban skies, I struggled to find all but the brightest guide stars. Later, I upgraded to a 9 x 50 finder scope, and my ability to see guide stars as indicated in my star atlas increased substantially.

Eyepieces

Just like different people prefer different telescopes, so, too, can eyepieces be a highly personal choice.

I began to introduce better eyepieces into my collection after being in the hobby for about a year or so after I had the chance to get my feet wet. That collection includes the following:

I really like all of these eyepieces and wouldn’t hesitate to recommend them to others. They are not the cheapest eyepieces out there, but they are not the most expensive, either.

For truly high-end eyepieces at truly premium prices, check out the offerings from Tele Vue.

Diagonals

Another worthwhile upgrade in the case of refractors and catadioptrics is a better diagonal. The diagonal that manufacturers often package with a scope is a bottom-of-the-barrel model that may act as a weak link in your optical chain. An excellent telescope used with an excellent eyepiece will ultimately perform poorly if an inferior diagonal is placed between the two. When the time comes to upgrade your eyepieces, you may also consider upgrading your diagonal if your telescope requires one.

I also dislike how some diagonals (and some Barlow lenses, too) have set screws that dig into eyepiece barrels and leave a little nick in the metal. I look for models with either a compression ring or a twist-lock feature that I increasingly see available.

Orion’s 1.25-inch Dielectric Mirror Star Diagonal
My 1.25-inch dielectric mirror star diagonal.

I use and recommend a version of the Astro-Tech dielectric mirror star diagonal, which is sourced from Long Perng, a manufacturer based in Taiwan. Something as mundane as a diagonal may not seem worth putting a lot of money into. But it’s worth it.

An internet search for dielectric mirror star diagonals will reveal numerous other options.

Next: Final Thoughts