Orion Apex 127mm Mak-Cassegrain Review: Now Discontinued

The Orion Apex 127 Maksutov-Cassegrain telescope was a great choice for astronomers on the go who wanted a lightweight, portable scope for viewing bright targets, though it didn't offer the best value for the money.
Tested by
TelescopicWatch
3.9
/5

Orion’s Apex 127 was sold primarily as a spotting scope, but it was identical to the “astronomical” 127mm Maksutov-Cassegrains sold by some other brands. If you didn’t mind the hassle of upgrading the accessories and choosing a mount for it, the Apex 127 really was an excellent telescope. It used the same optics as the Sky-Watcher and Celestron 127mm Maksutov-Cassegrains, as well as other former offerings from Orion, like the StarMax 127. 

The Apex 127 was a great option for anyone looking for an easy-to-carry telescope, and it was ideal for viewing the Moon, planets, and double stars. The small size of the tube allowed it to easily fit into a backpack, while the mounting requirements were not particularly demanding either. It had the versatility to be used with different mounts, such as a light-duty alt-azimuth mount, a small equatorial mount/star tracker, or even a decent and sturdy photo tripod with slow-motion adjustment and a fluid head. You can even carry it with one hand or put the tube in a backpack and sling the tripod over your back.

Sadly, Orion Telescopes ceased operations in mid-2024.

Orion Apex 127mm Maksutov-Cassegrain

What We Like

  • Excellent optics ideal for lunar, planetary, double star and some deep-sky viewing
  • Lightweight and compact
  • No need to worry about collimation, chromatic aberration, or coma

What We Don't Like

  • Aperture smaller than advertised, not much of a gain over 102mm
  • Mediocre supplied accessories
  • Not the best value for the money compared to similar offerings with different accessory bundles
Partially Recommended UK TelescopicWatch

At the price it commanded, the Orion Apex 127 really was a steal if you wanted a convenient, travel-friendly and portable telescope with enough aperture for some serious viewing. However, if you didn’t already have a mount and suitable star diagonal, the Sky-Watcher Skymax 127/AZ-GTi or Celestron NexStar 127SLT packages were a much better deal for the money than buying the bare Apex 127 optical tube and they come with better accessories while boasting identical performance otherwise.

Orion’s Apex 127 was sold primarily as a spotting scope, but it was identical to the “astronomical” 127mm Maksutov-Cassegrains sold by other brands. If you didn’t mind the hassle of upgrading the accessories and choosing a mount for it, the Apex 127 really was an excellent telescope.

Overview Of Apex 127mm

Orion Apex 127 Optical Tube
By Zane Landers

As with all of Orion’s 5” and smaller Maksutov-Cassegrains, the Apex 127 came with an extremely aesthetically pleasing powder coat finish with a pretty ruby-red colouration – why they didn’t do this with their 6” and 180 mm optical tubes I do not know. 

The Apex 127 has an undersized primary mirror around 120 mm (4.72”) across, which makes it half an f-stop slower – f/12.5 vs the f/12 advertised. This is the same as Celestron’s NexStar 127SLT and the “127mm” Maksutov-Cassegrains sold by Sky-Watcher, as well as any other 127mm f/12 Maksutovs out there.

I wish Orion and the other manufacturers who sell this same telescope could just be honest about this because it’s still a nice telescope otherwise. With 120 mm of aperture, you can see a lot of detail on the Moon and planets and do a fair amount of serious deep-sky viewing – though the long 1500 mm focal length and nominally 1.25”-only accessories limit the wide-field capabilities of this instrument.

Being a Maksutov-Cassegrain, the Apex 127 seldom needs collimation – though the rear cell has screws if you ever must do so. The optical quality of the Apex, like most Maksutovs, is superb. It is great for lunar, planetary, and double star viewing.

The Apex 127 focuses with the same moving-mirror system most catadioptrics use and comes with a Maksutov-thread visual back, though you can buy an adapter to use Schmidt-Cassegrain threaded accessories. The 1.25” visual back included has built-in T-threads to attach your DSLR camera. Attaching an SCT-thread adapter and a 2” SCT diagonal will result in some vignetting with wide-field eyepieces thanks to the scope’s narrow baffle tube and undersized primary mirror, but you can still use them to some extent.

Like most telescope optical tubes, the Apex 127 has a Vixen-style dovetail bar with ¼-20 holes attached so you can either attach it to a Vixen-compatible mount or a heavy-duty photo tripod.

Accessories

As it is sold primarily as a spotting scope and not an astronomical telescope for some reason, the Apex 127 is supplied with a 45-degree erecting prism diagonal. Not only is the 45-degree angled design rather uncomfortable for astronomical use, but the cheap erecting design results in scattering and light loss. You really should replace it with a 90-degree prism or dielectric mirror star diagonal if you plan on using the Apex 127 for any astronomical viewing.

Additionally, the Apex 127 includes an erect-image, straight-through 6×26 finderscope. Like the 45-degree diagonal, it’s really only useful for terrestrial spotting, as the erecting design sucks up a fair amount of the already paltry 26 mm of aperture. A quality 6×30 – or even better, 9×50 – straight-through or right-angle finderscope would be much better, and for a primarily planetary/double-star-orientated telescope like the Apex, a red-dot or reflex sight finder would also work just fine. You can easily swap in a new finder thanks to the StarMax’s industry-standard interchangeable, quick-release finderscope base.

The Apex 127 comes with one eyepiece: a 25 mm Sirius Plossl providing approximately 60x (the moving-mirror focusing system results in a slight deviation from the advertised focal length of the telescope depending on what diagonal/eyepiece combination you use). This is fine for low-medium power, but a 32 mm or 40mm Plossl eyepiece would probably be better for the lowest-power use, and you’ll want at least a couple short focal length eyepieces for high power, where the Apex 127 really excels.

Lastly, the Apex 127 includes a nice soft carrying case for transporting it, a convenient additional touch. The case has just enough room for you to stow a few additional small accessories, such as a diagonal, finderscope, and eyepieces, and it’s strong enough to withstand a fair amount of use.

Astrophotography Capabilities Reviewed

The StarMax’s f/12.5 focal ratio doesn’t really lend itself well to astrophotography. A few of my friends and acquaintances have actually taken some impressive pictures of the Orion Nebula and some other bright targets with this telescope, but it required an extremely heavy-duty mount and accurate autoguiding in addition to very long exposure times – a fast Newtonian or ED refractor is much, much better for deep-sky astrophotography.

The StarMax 127 does do a pretty good job for lunar and planetary astrophotography. With a 2x Barlow, a mount with motorised tracking, and a webcam-style CCD like the ZWO ASI120 or a Celestron NexImage series camera, you can get high-resolution images of the Moon and planets and amaze your friends and family, in addition to tracking planetary weather patterns and other phenomena.

Mounting Recommendations

At 3.9 kilograms, the Apex 127 is heavy enough that it demands a quality mount, particularly for the high-magnification use it is primarily designed for. An EQ-3 class mount like the Orion AstroView will certainly hold it, but an EQ-4 mount like the Celestron CG-4 would be even better. An alt-azimuth mount like the Explore Scientific Twilight I would also work fabulously and is a more convenient and lighter-weight option than an equatorial mount.

If you’re planning on doing astrophotography, plan on obtaining one of the aforementioned equatorial mounts and attaching a motor drive to it.

An amateur astronomer and telescope maker from Connecticut who has been featured on TIME Magazine, National Geographic, Sky & Telescope, La Vanguardia, and The Guardian.