Sharpstar SCA260 V2 260 mm f/5 Aspherical Cassegrain Astrograph

Sharpstar SCA260 Aspherical Cassegrain Astrograph

The Sharpstar SCA260 is designed for dedicated astrophotographers who want a telescope with large aperture and good speed to be mobile. Weighing 14.5 kg, the telescope is well suited for mounts such as the Skywatcher EQ6 or the Celestron CGEM. The SCA260 has an aspherical primary mirror and a spherical secondary mirror. The 3-element field corrector in the tube creates a large corrected field of view of 80 mm diameter. This even allows the use of full frame sensors.

The tube of the SCA260 is made of carbon fiber to keep the weight down and improve thermal performance. This maintains the focus better than a metal tube, even with temperature changes. The integrated fan with indicator cools down the primary mirror faster. The power supply is available separately.

The 3.35" focuser features dual speed for accurate focusing and four threads for custom adaptations: M90, M68, M54 and M48. The correct working distance (back focus up to 102 mm) is automatically maintained by the corrector built into the tube - if the image is sharp, the best possible field correction has been achieved.

The telescope is optimized for astrophotography. The use of 2" accessories is not intended. However, the working distance of 75 mm from the M48 thread allows the use of 1.25" accessories.

Additional service by TS - Optical and Mechanical Inspection

Each SCA260 undergoes a thorough optical and mechanical inspection upon arrival at Teleskop-Service. This service is included in the price.

The telescope will be cosmetically inspected.

The telescope is then mechanically inspected (main mirror and secondary mirror fit, focuser adjustment, etc.).

The following optical test is done at the optical bench in autocollimation. Here the collimation is checked. With a Ronchi eyepiece, the smoothness and the curve of the optics are checked. Not only the individual components are checked, but the entire system.

Each SCA is shipped with a complete checklist from Teleskop-Service.

Astrophotographic results obtained with this telescope on Astrobin

Here you can find some astrophotographs made with this telescope model: Link to Astrobin

Test of the SCA260 by Marc Khatchadourian

You can download the test report in PDF format here.

Astrophotographic results obtained with this telescope on Astrobin

Here you can find some astrophotographs made with this telescope model: Link to Astrobin

Test of the SCA260 by Marc Khatchadourian

You can download the test report in PDF format here.

The collimation of the SCA260:

Such a fast system needs a clean collimation to guarantee a good sharpness over the field. The collimation is similar to that of an RC.

1. Collimation of the secondary mirror:

The secondary mirror is collimated with the 3 collimation screws on the front. The secondary mirror has a center mark. This allows a clean collimation of the secondary. With tools, like the TSRCKolli, TSMKolli or Takahashi adjustment telescope it becomes easier.

2. collimation of the primary mirror:

There are three pull and three push screws on the back of the telescope. The tension screws are first loosened slightly, and then the pressure screws are used to collimate the primary mirror. Adjustment aids also facilitate the work here. The final collimation should be done on the star. An artificial star saves the awkward work at night.

Important: The primary mirror cell is very sensitive to pressure from the counter screws. If you are not careful, you will deform the mirror very quickly, so do not tighten the screws too much.