Sharpstar SCA310 Super Cassegrain Astrograph
The Sharpstar SCA310 is a 310mm-aperture, 1178mm focal-length f/3.8 astrograph built for high-speed deep-sky imaging. Its integrated triplet corrector, carbon-fibre tube and 55mm corrected image circle are designed for large-sensor astrophotography.
Sharpstar SCA310 key specifications
| Aperture | 310mm |
|---|---|
| Focal length | 1178mm |
| Focal ratio | f/3.8 |
| Corrector | 3-element corrector including ED glass |
| Image circle | 55mm |
| Tube | Carbon fibre |
| Focuser | 3.5-inch rack-and-pinion, 28mm travel, 1:10 fine adjustment |
| Rear connections | M68 / M54 / M48; M48 includes 2-inch filter thread |
| Back-focus range | 38–66mm |
| Weight | 23.5kg |

Fast f/3.8 deep-sky imaging
The combination of 310mm aperture and f/3.8 focal ratio is aimed at high-throughput imaging of nebulae, galaxies and other deep-sky targets. The optical system uses a large primary and secondary mirror together with a rear corrector rather than requiring a separate field flattener.
55mm corrected image circle
The integrated triplet corrector is specified for a 55mm image circle, providing coverage beyond a standard full-frame sensor. As with any large-sensor imaging system, final corner performance also depends on sensor tilt, spacing, focus and mechanical alignment.
Carbon-fibre tube and active cooling
The carbon-fibre optical tube is intended to reduce dimensional change as temperature varies. Three rear cooling fans help the primary mirror approach ambient temperature before and during an imaging session.
Focuser, rotator and camera connections
A 3.5-inch rack-and-pinion focuser provides 28mm of travel and 1:10 fine adjustment. The imaging train supports M68, M54 and M48 connections, while the M48 adapter incorporates a 2-inch filter thread. A 360° rotator allows camera orientation to be adjusted for framing.

Mount requirements
At 23.5kg for the optical tube, the SCA310 requires a mount with suitable imaging payload capacity after allowing for the camera, filters, focuser equipment, guiding hardware and other accessories. The supplied long Losmandy-style dovetail provides the mounting interface.
Sharpstar SCA310 UK
Dark Clear Skies supplies the Sharpstar SCA310 in the UK. The current price is £7,995 and this model is currently in UK stock. For a system at this scale, contact us if you would like to check mount capacity, camera format or imaging-train compatibility before ordering.
Frequently asked questions
What is the Sharpstar SCA310 designed for?
The SCA310 is a large-aperture, fast f/3.8 astrograph intended primarily for deep-sky imaging with large-format astronomy cameras.
Will the SCA310 cover a full-frame sensor?
Sharpstar specifies a 55mm corrected image circle, which is larger than the diagonal of a standard full-frame sensor. Final edge performance still depends on spacing, focus, sensor tilt and mechanical alignment.
What mount do I need for the SCA310?
The optical tube is listed at 23.5kg before adding the camera, filters, guider, focuser accessories and cables. Choose a mount with comfortable imaging payload headroom for the complete assembled system, not just the bare OTA.
Does the SCA310 need a separate field flattener?
No separate flattener is normally required because the optical design incorporates a rear three-element corrector. Correct back-focus and alignment remain important for best results.
How much is the Sharpstar SCA310?
The current Dark Clear Skies price is £7,995.
Planning an SCA310 imaging system?
Browse the Sharpstar range or contact Dark Clear Skies if you want us to check mount capacity, camera format and imaging-train compatibility before ordering.