Refractors are what most people think of when they picture a telescope, having a glass objective lens at the front and the focuser and eyepiece at the rear. However, refractors come in many shapes and sizes with different types of glass and different supplied mountings. They can be optimized for lunar/planetary, deep-sky, or astrophotographic use or with some overlap between.
Compared to reflectors and catadioptrics, refractors offer a number of advantages:
- Higher visual contrast – With no secondary mirror in the way and the ability to much more effectively control stray light, refractors offer much higher contrast than reflectors or catadioptrics, making them perform like a bigger telescope when used visually.
- Convenience – Refractors require no cool-down time or collimation, and do not have mirror coatings that degrade over time if left unmaintained.
- Tolerance of inexpensive eyepieces – Refractors do not have edge-of-field astigmatism or coma at low powers with cheap eyepieces like fast reflectors and catadioptrics do, meaning you can upgrade at a more leisurely pace and use cheaper eyepieces without sacrificing as much view quality.
- Wider fields of view – Small refractors tend to have wide fields of view and can achieve very low powers, making deep-sky objects easier to find. In addition, some deep-sky objects are so big and low in contrast that they are only visible in a small refractor.
- Ease of use when astroimaging – During long exposures with a refractor when astro-imaging, you need not worry about collimation shift or mirror shift.
However, refractors offer a number of disadvantages as well, including:
- Chromatic aberration – Lenses without extra-low-dispersion (ED) glass or extra lens elements cannot focus all colors to the same point. The result is chromatic aberration, which produces fuzzy images and purple halos around bright targets. This worsens with larger lenses and with faster focal ratios.
- Cost & nonavailability at large apertures – Refractors are much more expensive to get than the equivalent-aperture reflector or catadioptric. Furthermore, due to the difficulties and cost of making a large lens and properly mounting such a massive telescope, refractors are very seldom found above 6” in aperture, and those that are are extremely expensive and bulky instruments.
- Dew – Refractors have objective lenses that can dew up – though not as easy as the corrector lens on a catadioptric, thanks to their built-in dew shields.
This being said, a refractor – particularly a small one on an alt-azimuth mount – is unmatched in convenience. Finding objects is no problem thanks to the wide field, and even on a chilly night you can be out and observing in minutes or mere seconds. I myself always keep a small refractor by the back door of my house for spur-of-the-moment observing.
Ranking Best Refractor Telescopes According to Price & Features
1. Meade Infinity 80 - Lowest Price, Choice Under $150
The Meade Infinity 80 is an alt-azimuth mounted 80mm f/5 achromat, basically a clone of the Orion ShortTube 80 and is one of the cheapest good refractor telescope.
Being an 80mm f/5 achromat, the scope excels at low-power, wide-field views, even with relatively inexpensive eyepieces like the ones supplied. The simple pan-tilt alt-azimuth mount supplied with the Infinity scopes lends itself great to the Infinity 80, for wide-field views and Milky Way sweeping. The whole scope is also extremely lightweight at a mere 11 pounds (which I suspect is actually an overestimation) meaning you can easily pick it up with one hand. It’s also small enough that you can bring it as a carry-on on a plane.
Downsides? At f/5 and with rather inexpensive glass, the chromatic aberration of the Infinity 80 is pretty severe. At the 15x supplied by the included 26mm MA eyepiece you’re fine, but it slowly creeps in at 44x with the 9mm MA. The 6.3mm MA is unusable because of how cheaply made it is, and the image is beginning to break down at 63x anyway.
This is not a lunar and planetary instrument and you shouldn’t expect it to be. Sure, you can still see the craters on the Moon and the belts and moons of Jupiter, but don’t expect highly detailed lunar or planetary images. The included Barlow will do you no good expect if used with the 26mm MA for 30x.
The included star diagonal produces annoying spikes on bright objects, but at this scope’s price point I think it’s acceptable.
2. Meade Infinity 90 - Choice Between $150-$200
Like the Infinity 80, the Infinity 90 comes on the same alt-azimuth pan head mount and steel tripod, and with the same 26mm, 9mm, and 6.3mm MA eyepieces and inexpensive 2x Barlow.
The Infinity 90’s focal ratio of f/6.7 along with simply a better quality lens than the 80 means it is capable of significantly sharper views and higher magnifications. However, this means the included eyepieces and diagonal are the weak link of the telescope. The 26mm MA (23x) works quite acceptably as does the 9mm (66x). But the 6.3mm which would provide 95x has rather fuzzy images in addition to being uncomfortable to use. The 2x Barlow used in conjunction with the 9mm eyepiece will also not produce the best results. However, an aftermarket 6mm “gold-line” eyepiece is very inexpensive (under $35) and will produce sharp high-power views, so this is not a huge problem. Also, the Amici diagonal produces an annoying spike on bright objects and is largely plastic in construction. Replacing it with a quality diagonal will be $30, but you can live with the stock one until then.
Overall, a good choice, but you may need to upgrade some of the accessories.
3. Meade Infinity 102 - Choice Between $200-$275
The largest in the Infinity line, the Infinity 102 once again comes with the same alt-azimuth mount and steel tripod supplied with the Infinity 80 and 90, the same eyepieces and Barlow, and the same red-dot finderscope.
The Infinity 102’s focal ratio of f/6 means it’s largely suited for wide-field vistas, not high-resolution lunar and planetary closeups – it also seems to have an unusually high amount of chromatic aberration for a 4” f/6, which doesn’t help things. The same accessory issues mentioned previously, namely the cheap 6.3mm eyepiece and Barlow and the spike the Amici diagonal produces, still apply here as well. But otherwise, it’s a fine telescope.
Of the three larger Infinity scopes the 102 is overall my least favorite, but if you’re mainly looking to do deep-sky viewing and must have a refractor, it’s still a good choice.
4. Celestron Omni XLT AZ 102 - Choice Between $275-$400
The Omni XLT AZ 102 is possibly the most unusual instrument in Celestron’s lineup, but is a very good telescope for a very good price.
For starters, there’s the optics. While an f/6.5 and still an achromat, the Omni XLT AZ 102 has a surprisingly low amount of chromatic aberration. It also has Celestron’s StarBright XLT multicoatings which are at least in theory better than standard multi-coatings, allowing for maximum light transmission – in practice, the difference is probably negligible.
The Omni XLT AZ telescopes come with Celestron’s StarPointer Pro finder. It seems to be their attempt to compete with the Telrad, and has a similar design. However, the “bullseye” lacks the third, smallest circle featured in the Telrad which makes precise centering a little difficult and it runs on hard-to-find and annoying to change CR2032 coin cell batteries. It’s better than a standard red dot or 6×30 finderscope, however.
The Omni’s diagonal is an Amici like the Meade Infinity telescopes, but it’s much better made. As a bonus, it’s very ergonomically pleasing – Celestron found that in product tests people like to grab the diagonal and use it as a handle, so they designed the diagonal to be used that way. However, the “spike” on bright objects is still present.
The scope includes a single eyepiece, a 25mm for low-power cruising. However, thanks to the included 2” rack-and-pinion focuser you could add a 2” diagonal and wide-field 2” eyepieces for the best wide-field cruising experience, and you’ll of course want some short focal length eyepieces for lunar/planetary viewing.
The included mount is a little on the lightweight side, but I haven’t had any problems with it personally. It’s well-made and all-metal.
All in all, a pretty fabulous choice.
5. Explore Scientific FirstLight 102 w/Twilight I - Choice Between $400-$550, Author’s Choice
A personal favorite of mine and one of my first telescopes, the FirstLight AR102 w/Twilight I is an absolutely fabulous instrument.
The FirstLight 102 optical tube is absolutely flawless in its construction. Not only does is resemble the beautiful Japanese equatorial-mounted refractors of yore, but it has some of the best stray light control I’ve seen on any sub-$2000 refractor. The tube has many well-placed baffles on the interior and the dew shield is lined with a rubbery substance that even smells like a new car. The 2.5” hexagonal focuser is overkill for this telescope, and equally well-made.
Optically, the FirstLight 102 is extremely high-quality. Chromatic aberration is really only present on the Moon, Jupiter, Venus, and stars of first magnitude or brighter, and it doesn’t significantly affect sharpness. Deep-sky views are very high in contrast with pinpoint stars.
The Twilight I mount is an extremely high-quality mount that can easily hold up to a 6” Newtonian or catadioptric, or a 4” refractor, so the FirstLight 102 is about the largest telescope you can mount on it without vibration problems (Explore Scientific sells a 5” on the same mount but I do not recommend it). Motions are incredibly smooth and you can adjust the arm to be on either side or at any angle, as well as adjust the position of the slow-motion cables.
The only downside about this scope is the accessories. It comes with a 2” mirror diagonal, 25mm Plossl eyepiece, a red dot finder, and a suction-cupped smartphone adapter for lunar photography through the eyepieces. The diagonal is pretty good, and will work fine for a beginner. However, the eyepiece is almost entirely plastic, mediocre in optical quality, and the eye lens is recessed in the housing. As for the finder, it not only has a tinted window, but it wobbles on its mount to the point of unusability. I called ES asking for a replacement and received an even worse one. It really needs to be replaced with a Telrad or Rigel QuikFinder for you to actually aim the telescope with. The suction-cup smartphone adapter actually works really well but I’d be worried about my phone falling off.
Seeing as the accessories on most beginner scopes usually at least need supplementing anyway, I give this telescope my highest recommendation.
6. Orion AstroView 120ST - Choice Between $550-$800
The AstroView 120ST is the first telescope on this list with an equatorial mounting, as well as the first capable of any kind of astrophotography besides moon pictures with a smartphone.
A 120mm f/5 refractor, the AstroView 120ST is really a wide-field, low-power instrument. You can expect big purple halos and rather mushy images on the Moon and planets, and the image breaks down completely above around 90x. However, when equipped with a 2” diagonal and eyepieces or even the stock accessories the 120ST makes a fantastic deep-sky telescope, perfect for nebulae and open clusters.
The AstroView equatorial mount takes some getting used to, but it’s certainly acceptable for the 120ST optical tube. The extruded aluminum legs are not the steadiest, but they work fine. For motorized tracking and push-button slewing, you can equip Orion’s EQ-3M motor drive, which is also required for any kind of astrophotography.
As for astrophotography – it’s better than nothing, but don’t get your expectations too high. The scope’s chromatic aberration will cause halos around stars – particularly bright blue ones – and the mount is simply not up to the task of very long exposures, as it cannot be guided and the EQ-3M drive (sold separately but required for astrophotography) is not the most accurate.
The 6×30 finder included with the 120ST is not the greatest – a red dot finder would actually be preferable – but works fine. The 25mm and 10mm Sirius Plossls are high-quality and may be all you ever need, though a 2” diagonal and wide-field eyepiece would be best for low-power viewing.
If you aren’t interested in the Moon and planets and want to dabble in astrophotography, not a terrible choice.
7. Explore Scientific FirstLight 102 w/EXOS-2GT - Choice Between $800-$1200
This telescope is the same as the previously mentioned f/10 FirstLight 102, but on Explore Scientific/Bresser’s EXOS-2GT mount, a GoTo German equatorial with built-in tracking.
My previous comments about the optical tube still apply here. It’s one of the best achromats you can buy and an absolute killer on the Moon, planets and brighter deep-sky objects. The accessories, however, are still lacking and could use replacement.
The EXOS-2GT mount is more than adequate for visual use with the FirstLight 102 optical tube. Having GoTo and motorized tracking, astrophotography is possible. The Moon and planets can be photographed quite well with a CCD camera, particularly if you use a filter on the Moon and shoot in monochrome, which basically eliminates the remaining chromatic aberration. Deep-sky objects can also be photographed but chromatic aberration on bright blue and white stars is an issue, as is the scope’s slow focal ratio of f/10 – don’t expect too much.
The Bresser hand controller is a little weird to get used to – it’s not as intuitive as other manufacturers’ GoTo system – but it works just fine.
Overall a good, bargain choice for the visual user or casual astrophotographer.
8. Sky-Watcher ProED 80 w/AllView - Choice Between $1200-$1400
The Sky-Watcher ProED 80 features a Schott extra-low-dispersion (ED) front lens element, making it a semi-apochromat. This means that the chromatic aberration normally present in an 80mm f/7.5 achromat is reduced to a fraction of previous levels. It’s still there, but only faintly on the brightest stars.
The ProED 80 is not only great optically, but it is well-designed mechanically. The OTA comes with a 9×50 right-angle finder – overkill for such a small telescope, especially one on a GoTo Mount – and a dual-speed Crayford focuser.
The scope comes with a decent 2” star diagonal and a 25mm Plossl eyepiece. The 25mm Plossl is well-made and comes with an unusual twist-up eyecup, which is quite comfortable to use. More eyepieces for both low and high power use are recommended.
The AllView mount is not a common sight at star parties, but works well for the ProED 80. It also has some interesting features designed for it to be used with a DSLR or video camera during the daytime, if you’re interested in that.
The ProED 80 w/AllView is designed as a visual setup, but the ProED 80 optical tube is meant for astrophotography and the AllView is capable of exposures of up to 30 seconds, after which the tracking errors of the AllView and the field rotation caused by it being an alt-azimuth mount will become present.
The only real downside? At such a high price, you’re only getting 80mm of aperture. It’s up to you to decide if the GoTo and ED glass are worth a step down in image brightness.
9. Celestron Advanced VX 6 Refractor - Choice Between $1400-$1500, Best for Visual Astronomy
The biggest refractor on our list, and also the heaviest at about 75 pounds. A 6”, long-focus refractor is something an amateur a mere few decades ago would’ve killed for. Having a tolerable amount of chromatic aberration, enough aperture to seriously observe deep-sky objects, and high-contrast images with inky black backgrounds, a 6” refractor is enough for a lifetime of observing. The Advanced VX mount also offers GoTo and hands-free motorized tracking for maximum convenience.
Despite its weight, the Advanced VX mount can be taken apart into pieces weighing no more than 18 pounds each, and the C6R optical tube itself weighs about 20 pounds. However, the 4-foot (1.21 meter) long optical tube must be set on top of the mount with the tripod legs fully extended for maximum comfort while observing, which can be a bit of a pain.
The Advanced VX mount is not really capable of accurate enough tracking with a long, heavy telescope like the C6R on top of it to do deep-sky astrophotography, but the C6R will do a pretty good job for lunar and planetary CCD astrophotography, particularly if used with chromatic aberration-minimizing filters.
The Advanced VX 6 Refractor comes with a 1.25” prism diagonal and 25mm Plossl eyepiece as well as a 9×50 finderscope. The finderscope is arguably overkill for merely aligning the GoTo system with, but it’s a nice addition. You will of course want to obtain more eyepieces and possibly a 2” diagonal to get the most out of this big scope.
All in all a pretty good pick for visual use and semi-permanent setups, the Advanced VX 6 Refractor would be particularly ideal if kept on a dolly in a garage or shed and wheeled out for observing.
10. Orion Sirius ED80 EQ-G - Choice Above $1500, Best for Astrophotography
The Sirius ED80 EQ-G is the only telescope on this list that I can say with confidence is capable of serious deep-sky astrophotography right out of the box. Just plug in your DSLR or CCD camera and go.
The Orion ED80 optical tube is not really optimized for sharp, high-power visual use, with the lens design being more corrected to reduce bloating and halos around stars in astroimages, but it will suffice for the occasional casual observing session. Also, the Crayford focuser on the ED80 is a little simple for an astrograph, having no dual-speed capability and not being optimized for heavy loads, but it is adequate and can be replaced with a more expensive model relatively easy in a few minutes for under $200.
As for the Orion Sirius equatorial mount, you can read more about it in our in-depth review, but it’s the smallest and lightest mount we recommend for serious deep-sky astrophotography.
The Sirius ED80 EQ-G comes with an 8×40 finder – adequate for aligning the mount’s GoTo system – and a 25mm Sirius Plossl eyepiece, as well as a star diagonal.
If you’re looking to get into astrophotography with only one click besides buying an adapter for your camera, the Orion Sirius ED80 EQ-G is probably it.
Tips on choosing a refractor
- Focal ratio
Achromats at or below f/6 are guaranteed to have enough chromatic aberration to render them near-useless for high-power lunar and planetary views. So if you’re in the market for a refractor, only buy a fast achromat if you’re interested in wide-field views of star clusters and nebulae – not the Moon and planets.
- Achromats, Apochromats, and ED Doublets
Achromatic refractors pretty much always come with crown and flint glass lens elements. These work acceptably at longer focal ratios and with smaller instruments, but with fast focal ratios and large apertures – or for good astroimages – consider an ED doublet or apochromatic refractor. ED doublets, also known as semi-apochromats, use FPL-51, FPL-53, or FCD100 glass in one lens element to reduce chromatic aberration to acceptable – although not nonexistent levels, although for higher prices.
Apochromats use 3 or sometimes more lens elements in their objective, usually with at least 1 ED lens element. In addition to color control, adding more lenses can control edge-of-field aberrations better and lead for more pleasing astroimages with less field curvature and other issues which are particularly evident with large CCD chips.
Flourite doublets are seldom seen anymore and are very expensive, but offer near-perfect color control without the high weight of an apochromatic triplet or quadruplet by using a fluorite lens element. However, they are very expensive, and the fluorite element is more fragile than regular glass.
You Get What You Pay For
Cheap refractors are going to have more chromatic aberration, cheaper accessories, cheaper mounts, and lower build quality than a more expensive instrument. Some people pay five to ten thousand dollars – sometimes more – for apochromatic designs and fluorite doublets for perfect chromatic and other aberration control from the likes of Stellarvue, Astro-Physics, and Takahashi. However, for the hobbyist on a budget, a long achromat, ED doublet or inexpensive apochromatic triplet will more than suffice for visual use or photography with a DSLR or modest CCD camera.