SHARPSTAR SCA260 SUPER CASSEGRAIN ASTROGRAPH F/5
Available in September 2021
The Sharpstar SCA260 is an Aspherical Cassegrain astrograph with a fast focal ratio of f/5 and a focal length of 1300mm. This telescope features a 260mm aspherical primary mirror made of PZ33 borosilicate glass with a similar low expansion coefficient of the Pyrex. The enhanced aluminium mirror coating ensures a reflectivity of over 95%. The secondary mirror has a new lever adjustment function that can be moved in a horizontal position. The optical path includes a quadruplet air-spaced 3" field flattener optimized for full-frame photography with minimal vignetting. The heavy duty rack & pinion 3.2" focuser ensures smooth operation without slipping and the high capacity for accessories. The focuser is compatible with the ZWO EAF electronic focuser bracket.
The two M54×0.75 threads and M48×0.75 threads at the rear of the focuser can meet different needs, are convenient to connect to most commercially available imaging-terminal and achieve perfect focus. The optical tube is made of carbon fiber with CNC-machined aluminium parts for enhanced structural rigidity and durability, and features three cooling fans at the rear. -
-
CCDInspector plot showing the curvature of the SCA260.
| Optical design |
Aspherical Cassegrain reflector |
|
Primary mirror diameter |
260 mm |
|
Focal length |
1300 mm |
|
Focal ratio |
f/5 |
|
Secondary mirror |
Spherical, 120 mm (minor axis) |
|
Corrector rear group |
Quadruplet air-spaced |
|
Image circle |
80 mm |
|
Focuser |
Rack & pinion, dual speed (10:1) 3.2" diameter |
|
Resolving power |
0.46 arc second |
|
Stellar limiting magnitude |
13.8 |
|
Focuser |
Rack & pinion, dual speed (10:1) 3.2" diameter |
|
Camera connection |
M54 x 0.75 male, M48 x 0.75 male |
|
Corrector distance |
75 mm |
|
Tube weight |
15 kg |
|
Tube length |
712 mm |
|
Tube diameter |
280.5 mm |
|
Tube material |
Carbon fiber |
|
SKU |
SS-260CDK |
Eastern Veil Nebula - Sharpstar SCA260 Super Aspherical Cassegrain Astrograph