Used Telescopes Buying Guide – The Complete Guide

There are a lot of good reasons to buy a used telescope, especially right now. Given the current global economic crisis, many folks may not have enough money to buy the scope of the brand of their dreams new from the manufacturer.

There’s also the factor that buying used opens up a much greater range of products. If you want a manually clock-driven 8” Schmidt-Cassegrain, for example, the only way to get one is to buy used – Celestron and Meade haven’t made any since the turn of the millennium. Likewise, if you’re looking for a scope from your younger years such as a small Japan-made refractor, or an Edmund Astroscan, or a Coulter Odyssey. Some would say there’s little justification in buying new at all!

I buy a lot of used telescopes – it’s a bit of a mini-hobby for me. It’s allowed me to make a few bucks here and there, score great deals for friends, or add a piece of equipment to my collection that I otherwise might not have been able to. However, shopping effectively for a used telescope does take a lot more knowledge than simply clicking “buy” and entering payment information, and in this article, we’re going to go over some tips, tricks, and recommendations on how to find a good deal that fits your needs.

Finding a Used Telescope

There are about half a dozen websites where you can easily find a used scope: Cloudy Nights, Astromart, eBay, Craigslist (and equivalents such as Gumtree and Kijiji), and Facebook Marketplace. They all have different pros and cons.

  • Cloudy Nights is actually a full-fledged astronomy forum that I highly recommend joining. It has a Classifieds section that is vetted and well-administrated to ensure legitimate listings. Most of the sellers are knowledgeable astronomy enthusiasts, many of whom also frequent the forums. However, apart from any security features your preferred method of payment has (such as PayPal’s claims system or perhaps your bank) there is nothing preventing scams besides the good faith of the site administrators. I have only run into one questionable seller in the hundreds of purchases I’ve made on Cloudy Nights, and he shipped the item quite expediently once I reported him to the site administrators (after all, nobody likes being banned), so overall I consider it quite safe.
  • Astromart requires a $15 fee to use. While in many ways it resembles Cloudy Nights, it tends to involve more sales of high-end equipment due to the price barrier, so it’s usually not worthwhile to shop there if you’re looking for a first scope. Additionally, there are a lot more sellers who are quitting the hobby or selling gear on behalf of deceased relatives or friends so they may not necessarily be as knowledgeable about what you are buying. While the administration of Astromart is incredibly laid-back and does not seem to interfere as often in buyer-seller disputes as the CN administrators and does not moderate or approve listings before they are posted, the cost barrier of the site seems to prevent many scammers from appearing.
  • eBay is probably my least favorite place to buy telescopes, but also the best place to find deals. Most sellers are incredibly lacking in knowledge and will frequently do stupid things such as undercharge or overcharge for shipping (and demand extra money if the latter occurs), take terrible pictures, set absurd prices, and often will claim an item to be one thing when it is painfully obviously another (such as exaggerating aperture or claiming a scope to be a newer model). However, these same qualities are also what makes eBay such a gold mine for deals.
  • Craigslist and Facebook Marketplace along with similar local-classified style websites abroad are pretty self-explanatory. You’re a bit safer from stupidity since transactions tend to be cash and local pickup, but always inspect what you’re buying first.

What to (and Not to) Buy

Besides the telescopes we recommend that are still available new, the following are good choices for beginners shopping for used telescopes:

  • Celestron, Meade, Orion, and Sky-Watcher Schmidt-Cassegrains of almost any size, provided they come with a mount
  • Almost all refractors of 80mm or greater aperture
  • Almost all Maksutov-Cassegrains of 90mm or greater aperture
  • Almost all Dobsonians
  • 6” or larger equatorial pedestal-mounted Newtonian telescopes e.g. Meade Starfinder, Criterion RV6/8, Edmund and Cave telescopes

In general, don’t buy:

  • Cheap small refractors – even if they have good optics and mounts, the accessories on older scopes are often terrible and apertures smaller than 80mm can’t show you much
  • Small equatorially-mounted Newtonians – these tend to be undermounted and can be Bird-Jones scopes
  • Meade LX200 non-GPS telescopes – computer functionality is terrible and cannot be easily upgraded to Autostar
  • Celestron Ultima 2000 – These suffer from Y2K problems
  • Bausch & Lomb/Criterion Dynamax Schmidt-Cassegrains – these have terrible optics
  • Small ball-mounted Newtonians e.g. Edmund Astroscan – these have terrible optics and can’t be collimated
  • Celestron NexStar GT telescopes – these are poorly made in general
  • Meade DS-series telescopes – these are poorly made in general
  • Meade ETX-60 and ETX-70 – poorly made and too small
  • Vixen VMC-95 and VMC-110 – terrible optics
  • Almost anything made by Tasco, Bushnell, Vivitar, Seben, Gskyer, Gosky, or other generic or poorly-reputed brands
  • Anything that only takes 0.965” eyepieces
  • Anything that is brass or says anything about “power” on the box
  • Any of the telescopes we already rate below 3.9 stars on our site

This is by no means a comprehensive list; if you’re still unsure, ask around on astronomy forums or ask us.

Pricing of Used Telescopes

Generally, a used telescope or accessory that is still in manufacture and in good condition is worth no more than around 70 to 80 percent of its new price – e.g. an 8” Dobsonian that costs $500 new would sell for $350 to $400. Don’t hesitate to negotiate with a seller if they want as much as or more than the new price; the worst that can happen is you go somewhere else. If the scope needs cleaning or minor repairs, offer less than 60% of the new price.

For out-of-date scopes that are no longer made, figuring out whether a price is fair or what you should offer can be difficult. Check out the sold listings on Cloudy Nights, ask experienced astronomers for advice, or consult a buyer’s guide like Star Ware or Uncle Rod’s Used CAT Buyer’s Guide.

Evaluating Condition – Pictures

Obviously, it’s hard to get a good idea of how well a telescope works if all you have is pictures of it and the buyer’s assurances. In general, follow these pointers:

  • If there are any sort of electronics and the seller says they are “untested”, unless you see signs of severe corrosion they are likely to function just fine. However, don’t pull the trigger unless the seller offers returns. If they don’t and your purchase turns out to be a worthless doorstop, you could easily be out hundreds of dollars.
  • If it’s a mass-manufactured Dobsonian and there is exposed chipboard in the base, avoid. The base will rot very quickly.
  • If anything that’s not a screw or fastener is rusty, avoid.
  • If it’s a Schmidt-Cassegrain and the corrector is foggy, avoid. It may be coating failure which is impossible to remove or remedy.
  • If it doesn’t come with eyepieces and is supposed to, figure out how much a couple good eyepieces are going to cost you and then subtract them from what the scope would otherwise be worth.
  • If it’s a Newtonian and you think you can see through the mirrors or the reflective coating is missing, avoid.
  • If a part of the telescope is obviously missing and it’s not sitting beside the scope because the seller assembled it wrong, avoid.
  • If the objective lens or mirror is chipped, avoid.
  • If there’s what looks like fungal growth on the optics, it will probably come off with a good cleaning, but you should pay less because of the inconvenience of cleaning it.
  • If there’s dust/dirt on the telescope or optics, be prepared to pay less, but remember that a good rinse or wipe will probably solve most problems.
  • If the optics are scratched, the scope is worth a lot less money but probably will work fine, so if it’s a good deal or you can negotiate on the price by all means buy it.
  • Don’t assume anything is included with the telescope besides what’s in the pictures.

Evaluating Condition – In-person Inspection

If you do have the option to pick up your telescope in person, by all means, take it. Inspection can reveal a lot of important information that photos may not:

  • Does the telescope move smoothly? If it’s a Dobsonian, solving sticky, bumpy, or jerky motions may be as simple as loosening or tightening a screw or cleaning off the Teflon pads. If it’s a motorized scope, however, bumpy or jerky motions (even if any clutches are loosened) could indicate misalignment, corrosion, dirtiness or damage – while the problem is usually fixable at no cost just with some hard work, if you’re not mechanically inclined and don’t have some basic tools it may be difficult or next to impossible to do so.
  • Check the optics – as was mentioned before, if you see any evidence of chips or coating failure avoid buying, and if there are scratches consider negotiating the price down.
  • Always be sure that any electronics power on and function properly before paying.
  • Make sure all accessories that were promised in the ad/listing are included.

A Few More Important Tips

Warranties with telescopes are a bit of a complicated business. With some (typically high-end) manufacturers such as Explore Scientific, products come with a lifetime warranty that transfers between owners. With most manufacturers such as Celestron, generally, most repairs are done at the cost of the owner, and little in the way of a “warranty” necessarily exists. The one exception is Orion – they will not provide support or spare parts for any product that is not still in the hands of the original owner, so buyer beware (though this is generally only an issue if you are buying a computerized telescope or mount).

Older telescopes, provided they do not have GoTo, differ little from modern instruments. Other than improvements in computers, mount design changes, and slight updates to optical coating and testing technology, nothing has drastically changed in telescope manufacturing for well over half a century. A Celestron C8 from 1970 is functionally identical to one from 2020, though the latter usually has slightly better coatings and may deliver images a few percent brighter. A Dobsonian from 1985 that does not have any damage will perform identically to one made yesterday afternoon. The simple motor drives on many older equatorially-mounted telescopes typically work just fine after decades provided they have not been subjected to gross mistreatment, and are usually easily replaced if they stop functioning. And in most cases, modern eyepieces and accessories adapt with little to no effort to almost any older telescope.

Cleaning old telescopes is generally pretty straightforward. For the exterior of the tube and mount, use common sense and simple paint-safe cleaning products. For lenses and mirrors, simply use a rinse of distilled water and light dish soap – avoid using any sort of wipe as this can cause scratches. A more in-depth overview of how to clean telescope optics can be found here.

Summary

While buying a used telescope can often lack the thrill of opening a fresh product out of fancy packaging or the satisfaction of having a beautiful, functional instrument immediately, it can get you something that is either unaffordable or unavailable new and save you a lot of money!

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