Best Planetary Telescopes – Reviews & Buyer’s Guide

This review is geared mostly towards imagers – for visual use, the only things really important about choosing a telescope for planetary viewing are that it has good optics, a sturdy and easy to move mount, and as large an aperture as possible (AKA most Dobsonians). However, all of the telescopes listed in this review are plenty good for visual.

While GoTo is obviously not really needed to find the planets, with GoTo comes tracking, and with tracking comes a lot of convenience – it’s pretty much required for planetary imaging, as nudging the telescope along manually tends to cause vibrations ruining your capture and can put the target outside the field of view of your camera. Thus, many of the planetary telescopes recommended here are GoTo.

Ranking Planetary Telescopes According to Price & Features

1. Celestron 90SLT - Lowest Price, Choice Under $400

The Celestron 90SLT (Star Locating Telescope) is relatively small, and thus you’re not going to be doing too much serious imaging with it. However, the scope is incredibly lightweight and portable, has a relatively sturdy GoTo mount, and has a nice long focal ratio of f/14.

The 90SLT is the same optically as the popular C90 optical tube Celestron sells as well as most Chinese-made 90mm Maksutovs on the market. Designed to emulate the legendary Questar 90mm, these telescopes are incredibly high-quality optically and suffer from relatively little image shift. Being Maksutovs, they also do not require collimation, making them low-maintenance and fast to set up.

The included eyepieces with the 90SLT are Kellners – a 25mm (50x) and 9mm (139x). While not the highest in quality, at f/14 they operate just fine – though you’ll want to upgrade to Plossls or modern wide-field eyepieces later on.

The 90SLT’s mount suffers from some flaws, however. For one, the gears aren’t super high quality and they tend to “tick” when tracking – meaning that your target will bounce around the field of view sometimes. This is not a problem for visual use, but can be a nuisance for imaging. Second, its light weight means it is incredibly prone to being bumped. This will ruin the GoTo system’s alignment and thus tracking, requiring a full re-start of the system before you can proceed.

Pros

  • Great optics
  • No collimation needed
  • Long f/14 focal ratio
  • Lightweight & portable

Cons

  • Lightweight mount is prone to being bumped
  • Cheap mount gears

2. Celestron NexStar 5SE - Choice Between $400-$650

The Celestron NexStar 5SE (“Special Edition”) is a Schmidt-Cassegrain, so it has a shorter f/ratio than most Maksutovs (f/10) and thus will need a stronger Barlow for good planetary imaging, and slightly shorter focal length eyepieces to achieve the same given magnification as a 5” Maksutov would.

Being a Schmidt-Cassegrain, the 5SE also requires somewhat frequent collimation, which requires doing it on a star in the field and can be quite challenging even to experienced users. However, good collimation is crucial for sharp views and photos – I have heard many stories of people dismissing their Schmidt-Cassegrain as “bad” optically only to find it to be out of collimation.

The 5SE comes with Celestron’s StarBright XLT multi-coatings for maximum light throughput.

The 5SE’s mount is quite sturdy and has gearing of reasonably high quality. However, its built-in wedge, which would eliminate field rotation in planetary images and allow for some deep-sky astrophotography, is almost entirely useless, lacking fine adjustments in latitude and with zero adjustment capability in azimuth at all.

The 5SE’s relatively large secondary mirror – covering 37.8% of the scope’s diameter – also reduces contrast by spreading out the Airy disk, making fine details harder to spot visually. For imaging, this is not much of an issue.

The 5SE also comes with only a single eyepiece – a high-quality 25mm Plossl providing 50x, not particularly useful for planetary viewing. However, this can be forgiven as most telescopes require additional aftermarket eyepieces anyway.

Pros

  • Enough aperture for serious viewing/imaging
  • Sturdy mount
  • Good optics

Cons

  • Needs collimation, a difficult task
  • Large secondary mirror
  • Useless wedge

3. Celestron NexStar 6SE - Choice Between $650-$900

The NexStar 6SE is basically the “big brother” to the NexStar 5SE, and pretty much all of the same critiques and features apply.

However, the 6SE optical tubes tend to be slightly higher in optical quality than their 5SE counterparts. The 6SE also has a beefier, sturdier mount than its sibling, with no silly built-in wedge. Lastly, the 6SE has a smaller central obstruction percentage-wise of the secondary mirror, leading to sharper and higher-contrast images.

Like the 5SE, the Celestron NexStar 6SE does require collimation every once in a while – and it should of course be checked every time you take it out.

The extra inch of aperture (for only slightly more money) of the 6SE is really not something that should be overlooked. While it does result in a larger, heavier instrument, you gain an extra 20% in resolution (and also 44% in light-gathering power) compared to the 5SE, which is quite noticeable visually and in images. This also makes the 6SE a good general-purpose telescope, as the GoTo is enough to actually start being useful and the aperture is large enough to show a fair amount of deep-sky objects. Like the 5SE, the NexStar 6SE comes with Celestron’s premium StarBright XLT multi-coatings, further amplifying the light-gathering power.

Overall, if you’re pretty interested in planetary imaging but still want a lightweight, portable telescope and want to do at least some deep-sky observation, this would be my pick.

Pros

  • Useful for deep-sky observation too
  • Decent aperture

Cons

  • Needs collimation

4. Meade 6” ACF LX65 - Choice Between $900-$1050

A relative newcomer to the market, the 6” Meade LX65 is somewhat akin to a very beefed-up Celestron NexStar 6SE.

The 6” LX65 has Meade’s signature Advanced Coma Free optics and UHTC coatings. The ACF optics are a nice feature for general deep-sky observation as the design cleans up the edge of the field of view of aberrations, but for planetary viewing it doesn’t matter all that much. The UHTC coatings are pretty similar to the StarBright XLT coatings that Celestron supplies on their telescopes, likewise providing a few extra % in light-gathering ability that would otherwise be reflected or absorbed.

The LX65 mount is quite sturdy. So sturdy, in fact, that Meade claims you can put another telescope on it and even provides a dovetail saddle to do so. I wouldn’t really bother attempting this, but it’s a nice bonus, I suppose. It also comes with a built-in handle (nice) and I like the placement of the hand controller rack.

In general, the LX65 has a higher-quality fit and finish than most lower-priced telescopes, with next to zero plastic. It feels industrial and well-made. The scope seems to have less image shift than its Celestron counterpart, and collimation tends to hold a little better.

The only large downside of all this is the scope’s weight. At 37.8 pounds, it’s almost twice as heavy as the Celestron NexStar 6SE.

The supplied eyepiece with the LX65s is a single, cheap 26mm Plossl (59x). For a telescope priced around $1000, I would’ve appreciated an at least slightly higher quality eyepiece.

Pros

  • Decent aperture
  • Can hold another telescope on the same mount
  • Very sturdy & well-made

Cons

  • Cheap included eyepiece
  • Heavy

5. Celestron NexStar 8SE - Choice Between $1050-$1250

Like its smaller counterparts, the Celestron NexStar 8SE features good Schmidt-Cassegrain optics with StarBright XLT multi-coatings and the same version of the SE mount as the 6SE.

Having 8” of aperture allows for professional-quality planetary images and for quite good views. An 8” scope will also do wonders on deep-sky objects, should you decide to express interest in that part of the hobby.

The 8SE does need collimation, however, and still comes with a lone 25mm Plossl eyepiece (80x). However, Celestron sometimes bundles this scope with their 1.25” eyepiece and filter kit and/or other accessories for no additional price.

The main flaw of the NexStar 8SE is that it is starting to hit the limit of what the mount can hold and can be a little shaky with the tripod legs extended all the way. However, in most cases this is acceptable.

All in all, the Celestron NexStar 8SE is a good general-purpose scope, just like its smaller brethren.

Pros

  • Large aperture
  • Useful for deep-sky observation

Cons

  • Needs collimation
  • Not the steadiest

6. Explore FirstLight 152mm Maksutov-Cassegrain w/Exos2GT Mount - Choice Between $1250-$1600

The Big Mak.

While still a 6” telescope, the Explore FirstLight 152mm Maksutov-Cassegrain w/Exos2GT Mount (now that’s a word salad) boasts a number of advantages over the prior-mentioned 6” Schmidt-Cassegrains.

For one, it’s a Maksutov. Maks tend to have slightly better optics and smaller secondary mirrors than their SCT counterparts, and the focal ratio is longer – f/12.5 versus f/10.

The FirstLight 152MCE2GT is very unusual among Maksutovs and catadioptric telescopes as a whole in one big, defining way: Its focuser. Unlike pretty much all SCTs and MCTs on the market, the FirstLight 152MCE2GT’s focuser is not an internal moving-mirror one but rather an external Crayford focuser. This means that you don’t have to deal with any sort of image shift, a huge boon for both visual and photographic usage. And it’s not just any fast-food Chinese Crayford, but rather Explore Scientific’s premium 2.5” hexagonal focuser – probably overkill for this scope, if anything.

Also unlike most other catadioptrics, the FirstLight 152MCE2GT sits in adjustable tube rings rather than simply having a bolted-on dovetail. The rings also have a massive carry handle at the top, which makes carrying the roughly 14-pound optical tube easier.

The EXOS-2 GT mount has a rather primitive hand controller, but it’s rock solid with the 6” Maksutov optical tube. Also, being a German equatorial design rather than an alt-azimuth, you won’t have to deal with field rotation like with the other telescopes preceding the FirstLight 152MCE2GT on this list.

The only cons about this telescope? For one, the supplied 26mm Plossl eyepiece (73x) and red-dot finderscope are absurdly cheap – the Plossl has a recessed eye lens and is largely plastic, and the red dot finder has a tinted screen and is hard to align.

The Exos-2GT mount’s hand controller is not quite as easy to navigate as Celestron or Meade units. Also, the instruction manual is extremely primitive and inadequate to explain the assembly and operation of the FirstLight 152MCE2GT – it is one page, and has hardly any text.

Unlike with an alt-azimuth mount, you’ll need to polar align the Exos-2GT – though you can polar align it and have the mount automatically track without aligning the GoTo if you wish.

But the biggest problem, no doubt, is the telescope’s weight. At a hair under 70 pounds, this is not a “grab n’ go” telescope. Thankfully, the mount can be taken apart and the heaviest single component of the whole setup is less than 20 pounds. Setting the telescope up if you dismantle it this way, however, will take a while.

That being said, the Explore FirstLight 152mm Maksutov-Cassegrain w/Exos2GT Mount is such a great planetary imaging rig out of the box that I am willing to overlook the massive weight.

Pros

  • Crayford focuser means no image shift
  • No collimation required
  • German equatorial mount means no field rotation

Cons

  • Complex operation and setup
  • Not as much aperture for your buck
  • Heavy

7. Celestron NexStar Evolution 8 - Choice Above $1600

Probably the only truly 21st-century telescope on this list, the Celestron NexStar Evolution 8 is probably an instrument I’d have myself were it not for the fact that I already have a barn full of scopes!

The Evolution 8 has the same C8 optical tube and NexStar hand controller as its less-expensive counterpart the NexStar 8SE, but it’s got two major tech upgrades.

For one, it has a built-in lithium-ion battery. Every other telescope on this list is going to require a 12-volt DC power supply of some kind, except for the Evo 8. Not having to carry around a big bulky battery, nor worry about the cord wrapping around your telescope or tripping over it is a godsend. I cannot express how awesome this feature is.

Second, you can control it with your smartphone or tablet. As even with a red filter on your phone or tablet will still be bright enough to ruin your dark adaptation, consuming precious phone battery out at night in the middle of nowhere is probably not the smartest idea, and having to provide the WiFi network will drain the scope’s battery faster, I would not really recommend bothering with this feature.

Like all SCTs the Evolution 8 will need collimation, but this is an acceptable inconvenience. The Evolution 8 is also reasonably lightweight – 38.5 pounds assembled.

Lastly, the Evolution 8 comes with two eyepieces – a 40mm (51x) and 13mm (156x) – both Plossls of quite high quality.

The Celestron NexStar Evolution 8 is a great telescope for pretty much everything, including planetary observing/imaging.

Pros

  • Large aperture
  • Lightweight and built in battery
  • Decent supplied eyepieces

Cons

  • Expensive
  • Needs collimation

Honarable Mentions

1. Celestron Astro Fi 102mm Maksutov

While offering more aperture than the NexStar 90SLT at basically the same price, the Astro Fi 102 has slightly inferior included eyepieces, and requires that you control it with a cell phone or tablet. This causes it to consume more electrical power. Having the same mount as the 90SLT, the scope is also prone to being bumped and the tracking is a little sub-par.

Users have reported a lot of problems operating the scope with their phone or tablet, but it’s hard to tell whether it’s from inexperience or if the SkyPortal app or telescope is actually giving them problems. It’s up to you to decide whether taking the risk on this is worth it.

All in all, a bit of a risky bet but one that could pay off, and if you really don’t want to spend more and don’t mind having to operate it with an external device I would give it a shot.

2. Orion StarMax 127

If you are on a budget but want a 5” Maksutov-Cassegrain, the StarMax 127 will work. It’s lightweight and comes on Orion’s AstroView EQ4 German equatorial mount. The scope also comes with a soft carrying case.

The StarMax’s supplied finderscope – a 6×26 erect image unit – is almost entirely useless. However, it is easily replaced with a red dot or larger finderscope thanks to the interchangeable standard finder shoe on the optical tube.

For motorized tracking (required for photography) the StarMax 127 does require a motor drive from Orion, which will cost between $100-$200 depending on whether you want single-axis or dual-axis motions. Overall the scope isn’t the most economical, but if you’d like a computer-free instrument it’s one of the few out-of-the-box kits that will do the job.

3. Meade LX65 5” Maksutov-Cassegrain Telescope

The 5” Maksutov LX65 is a little smaller and a little less expensive than the 6” ACF LX65. However, it is still on the same mount, and thus doesn’t way as much less as you’d think.

With an f/15 focal ratio, the 5” LX65 is quite good for lunar and planetary imaging. Being a Maksutov the scope needs no collimation – another advantage to consider. But it loses a significant amount of light-gathering ability and resolution compared to its 6” counterpart.

Recommended, but there are better options in the same price range.

4. Explore Scientific FirstLight 127mm Maksutov with Exos-2GT Mount

You’d think that this scope would be a scaled down version of the 6” Exos-2GT FirstLight Maksutov, but it isn’t. Having the same optical tube as the Meade 5” LX65, the FirstLight 127MCE2GT comes across as a scope that isn’t particularly cost-effective. The mount is very much overkill for the scope, and thus like the 5” LX65 it’s an overbuilt telescope with only minor advantages over some of its lower-cost competitors, some of which even have larger aperture.

Like the 5” LX65, not a terrible telescope, but not a particularly economical one either.

5. Sky-Watcher 8” Collapsible Dobsonian

Even in the realm of planetary imaging, Dobsonians still provide the best bang for your buck.

The Sky-Watcher 8” Collapsible is significantly cheaper than an 8” GoTo Schmidt-Cassegrain. Being a Newtonian, collimation is much easier than with a Schmidt-Cassegrain, though it is needed more often. And it’s basically the same portability-wise.

For visual use, you can set the Sky-Watcher 8” Collapsible up without aligning the GoTo. You can also slew the scope across the sky without ruining the GoTo alignment thanks to the scope’s dual-encoder technology, which allows you to save power or simply use the scope manually whenever you feel like it.

However, this all comes at a price. For one, the scope’s large size means it will consume more power when tracking. Second, the scope’s fast focal ratio means it will need a very strong Barlow to bring it to the necessary focal ratio for imaging. Lastly, “cord wrap” is far more of a problem than with a smaller telescope.

If you’re looking to save money and are more visual-oriented than imaging-oriented, however, I can highly recommend the Sky-Watcher 8” Collapsible.

6. Meade LX65 8” Advanced Coma-Free

The 8” ACF optical tube is a really nice scope – slightly better than Celestron’s standard 8” OTA – thanks to its ACF optics. Also, the optical tube has a convenient carry handle on the back.

However, the LX65’s tripod doesn’t carry the tube/mount head assembly as well as you’d think. Also, it is not available with the same extra accessories that Celestron sometimes bundles with their NexStar 8SE. Thus, I am hesitant to give it a firm recommendation.

7. Celestron NexStar Evolution 6

Most of my comments about the Evolution 8 apply here, except that it’s a 6”. Like the 8” Evo, the built-in battery and light weight are very nice, even if the WiFi controllable function is impractical. However, for the same price of the 6” Evolution you could buy a slightly less convenient – albeit more capable – 8” telescope.

Tips on Choosing the Best Planetary Telescope

  • Photography or visual?

If you don’t have any interest in photography, a simple Dobsonian will suffice for visual-only planetary viewing, and provides far more convenience and bang for your buck. However, for purely imaging or combined photographic/visual capability a catadioptric or Dobsonian with GoTo is probably what you want.

Also, while a refractor is great for visual planetary observation, particularly with a long focal ratio to minimize chromatic aberration or false color, with the exception of very expensive apochromats they are largely useless for planetary photography. Chromatic aberration in photos is far more pronounced and will probably ruin them. Thus, a Newtonian or catadioptric is best for planetary imaging – and either also provides much more aperture for your dollar than a refractor.

  • Focal Ratio

For planetary imaging, focal ratio is extremely important. You typically want to have a focal ratio between f/20 and f/30. Why, you might ask? It’s because you want a good image scale – that is, for your target to to take up as many pixels as possible on your camera chip (up to a certain point) for maximum resolution.

A Newtonian/Dobsonian with an f/5 or f/6 focal ratio will need a 5x Barlow or stacked weaker Barlows to achieve the necessary image scale for planetary imaging. However, there aren’t many choices for 5x Barlows on the market, they’re almost entirely useless for visual purposes, and a good one is quite expensive. Stacking Barlow lenses on top of each other will work, but it degrades the image quality somewhat and may cause focus/balancing issues.

A catadioptric, on the other hand, with a focal ratio between f/10 and f/15, only needs a 2x or 3x Barlow to achieve the necessary image scale for planetary imaging. These Barlows are far more frequently available, and can also be used for visual astronomy as well.

For visual use, focal ratio doesn’t matter much, except that a catadioptric will perform better with cheaper eyepieces than a fast Newtonian due to the long focal ratio having a steeper light cone, which is less demanding of the eyepieces optically.

Author Bio

Jason Cook

Jason Cook

As a planetary astronomer, I was working on the New Horizon project at Southwest Research Institute until mid 2016. Currently, I share my astronomical knowledge on this blog and I'm heavily into urban farming too.

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