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Celestron
Celestron CGEM II 8 SCT
The CGEM II is Celestron's mid-range computerised equatorial mount paired with their proven 8-inch SCT optical tube. The CGEM II mount is a significant step up from the NexStar SE's alt-az platform — it is a proper German equatorial mount rated to 18kg payload, capable of unguided astrophotography exposures and serious visual observing sessions lasting hours. The 8-inch SCT gives you 2032mm of focal length in a tube that is less than half a metre long. Planets at 250× are detailed and stable; deep-sky objects through a reducer look photogenic and rich. This is the configuration that dedicated amateur astronomers graduate to after outgrowing their first setup.
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What you'll see
These forum discussions do not contain owner reports of what is actually visible through the Celestron CGEM II 8 telescope. The threads are dominated by technical discussions about mount compatibility, tracking accuracy, and astrophotography performance metrics (periodic error, guiding, imaging quality). While one thread mentions an AP 130 EDFS refractor being used on a CGEM mount where it 'acts like it was made for it' and provides 'stable' views, there are no specific descriptions of celestial objects, planetary detail, deep-sky targets, or visual observing experiences unique to or characteristic of the CGEM II 8 itself. The forum conversations focus almost entirely on mechanical and electronic performance rather than the visual experience of observing through the telescope.
Worth knowing before you buy
Mount head feels heavy and unbalanced when used with the CGEM II despite the scope being stable; dovetail and rings must…
CGEM II has poor native periodic error of 15-30 arcseconds peak-to-peak, which is 3-6 times worse than competing mounts…
CGEM II has low declination guiding performance with slow correction when declination reverses, taking more than 5-10 se…
Head to head
How it compares
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Full Specifications
Optics
| Aperture | 203mm |
| Focal Length | 2032mm |
| Focal Ratio | f/10 |
| Optical Design | Schmidt-Cassegrain |
| Coatings | StarBright XLT multi-layer coatings |
Mount & Tracking
| Mount Type | GoTo (Computerised) |
| GoTo (Computerised) | Yes |
| Tracking | Yes |
Focuser
| Focuser Size | 2" |
| Focuser Type | SCT rear-cell focuser with reducer thread |
Physical
| OTA Weight | 5.4kg |
| Total Weight (with mount) | 34kg |
| Tube Length | 432mm |
| Tube Material | Aluminium |
Included Accessories
| Eyepieces | 40mm eyepiece |
| Finder Scope | 8x50 right-angle finder scope |
| Diagonal | Yes |
Smart Telescope Features
| Built-in Camera | No |
| App Controlled | Yes |
| WiFi | No |
| Battery Included | No |