Celestron CPC 800 GPS Review
- •8” Aperture Sufficient For Lunar, Planetary, And Deep-Sky Viewing
- •Simple Assembly, Easy To Set Up
- •GoTo And Motorized Tracking Functionality
- •Great Optics For Planetary Imaging Along With Visual Observation
- •Not Compact Or Easy To Store
- •Long Focal Length/Narrow Field Of View
- •Not Very Good For Deep-Sky Astrophotography With Long Exposures
- •Expensive For What You Get
The Celestron CPC 800 GPS is a rather bulky telescope for its aperture, but it’s packed with performance and versatility.
Celestron’s famous C8 optical tube has been offered in a fork mount configuration since its creation in 1970. The CPC 800 is the last remnant of that legacy, as all other C8 configurations Celestron now sells are on single-armed forks or German equatorial mounts. The CPC 800 is a fairly capable and portable telescope, though rather long in focal length compared to a typical 8” Dobsonian. You don’t get as much convenience as, say, the NexStar Evolution 8 out of the box, but the CPC 800 can be adapted for some deep-sky astrophotography and is quick to set up.
The C8 Optical Tube
203mm (8″) Aperture
2032mm Focal Length
The C8 optical tube has been a mainstay of Celestron’s product line since 1970. It’s an 8” (203mm) Schmidt-Cassegrain with a resulting focal length of 2032mm, which is achieved by “folding” the optical path with a concave spherical primary mirror and a convex secondary mirror that essentially magnifies the f/2 curve of the primary mirror. You focus with a knob on the back that moves the primary mirror along a rod inside the telescope tube, and attach accessories, such as a star diagonal or camera adapter, to the back. The C8 XLT offered with the CPC 800 can be converted to an f/2 Schmidt camera system using Starizona’s HyperStar corrector, which installs in place of the secondary mirror. You can also get an f/6.3 reducer to make the C8 better suited for deep-sky astrophotography.
The CPC Fork Mount & Tripod
The CPC fork mount is an alt-azimuth, GoTo design which can also be converted to an equatorial mount using Celestron’s equatorial wedge (sold separately). You can technically aim the CPC manually by unlocking the clutches, but only with the scope powered off, and it’s generally not a good idea to do so anyway. To set up the scope, you simply put the tube/fork combination on top of the tripod, and align it with a few stars that the computer system uses as reference points. The GPS in the mount saves you a few seconds by automatically updating the scope’s location as well as the date and time.
The CPC 800’s fork mount uses all-metal internal gears and tracks quite accurately – you’ll have no trouble centering your target every time, tracking for planetary astrophotography is pretty good, and the mount has an autoguider port for deep-sky astrophotography too.
The CPC 800 GPS includes a pretty basic set of accessories. You get a 9×50 straight-through, magnifying finder scope to aim the telescope at alignment stars, a 1.25” screw-on visual back, a 1.25”, all-metal prism star diagonal, and a 1.25”, 40mm “E-Lux” Plossl eyepiece providing 51x magnification with the CPC 800 and a true field of view just around ¾ of a degree across – or about 1.5 times the angular diameter of the full Moon. Additional eyepieces will provide varying levels of magnification (the CPC 800 can handle up to 400x on a steady night) and a 2” star diagonal and eyepieces or f/6.3 focal reducer would allow you to get a wider field of view than is possible with the limitations of the stock visual back and eyepieces.
What can you see?
The CPC 800 is pretty capable, as is any good 8” telescope. You’ll be able to see plenty of interesting Solar System and deep-sky objects.
Here’s what you can expect to see on the Moon and planets with the CPC 800:
Mercury and Venus don’t show any detail besides their phases in any backyard telescope, but Mercury is easier to resolve with the CPC 800 than smaller telescopes.
The Moon shows details mere miles across, and appears jaw-droppingly bright and crisp at any magnification.
Mars’ polar ice caps and any dust storms are immediately apparent with the CPC 800 at medium or high magnification; when Mars is at its closest to Earth a few dark markings on its surface can also be seen.
Jupiter’s cloud belts are colorful and the Great Red Spot can be seen on a steady night. Jupiter’s 4 large moons appear as disks at high magnification with the CPC 800, and you can see their shadows when they transit across Jupiter too.
Saturn’s rings are readily apparent at any magnification; high power with the CPC 800 will show the Cassini Division within them, some cloud belts, and a handful of moons.
Uranus’ disk can be resolved with the CPC 800, but its moons are too faint to see even under dark skies.
Neptune is hard to distinguish from a star with the CPC 800, but you can see its faint moon Triton accompanying it.
Pluto can be seen as a star-like dot under dark skies if you can figure out which one of the hundreds of points of light in your field of view it is.
What you can see with the CPC 800, or any telescope, when it comes to deep-sky objects is heavily dependent on the severity of your local light pollution conditions. You’ll be able to view star clusters and nebulae under city skies, and resolve globular clusters; dark skies will allow you to see dust lanes in bright galaxies as well as more detail in nebulae like the Orion Nebula (M42).
Heavy & Large
The CPC 800 is more expensive than the 8” NexStar Evolution, which has the ability to be controlled via your smart device (whereas the CPC is not). The CPC 800 is also rather heavy – the tripod weighs 19 lbs by itself, while the scope/forks are inseparable and weigh a whopping 42 lbs! This makes for a sturdy setup – and assembling the scope is easy with only 2 parts – but you should be sure you can accommodate it. The wide footprint of the CPC 800 and its fork mount also makes storage a little tricky. However, if you can put up with these issues you’ll be rewarded with a super-sturdy and capable instrument.
The Celestron CPC 800 GPS isn’t for everyone, but it’s a versatile and well-made scope with a variety of capabilities. We would definitely recommend it if you have the budget and storage space for one.