More about the series RASA...
Digital Schmidt camera for wide angle astrophotography!
This astrograph makes it very easy to create stunning photos with a modern DSLR or astronomical CCD camera. The new optical design has a four-lens corrector, incorporating rare earth glass, which suppresses chromatic aberrations and other problems such as coma and field curvature. Never before has an astrograph in this price range delivered such optical quality and spot size over the entire image field. The design also allows for a very low vignetting.
- super-fast 11" f2.2 optics - sharply images APS format and is even optimized for sensor sizes up to a 70mm field diagonal.
- extremely short exposure times - the RASA Astrograph acquires images twenty times faster than at f10! Thirty seconds at f2.2 correspond to ten minutes at f10 - tracking control is hence superfluous!
- huge field of view - with a 620mm focal length, makes wide-angle shots a piece of cake and you and always have an overview
- excellent focusing mechanism - new bronze bearings reduce image shift, the 10:1 FeatherTouch micro-focuser allows highly precise focusing!
- innovative Features - quieter 12V MagLev fan reduces the cooling phase, keeps out dust and allows optimum air circulation in the OTA. Various adapters for popular camera brands are included. Back focus for the camera supplied adapters: 55mm, back focus for the front lens group: 69.26mm
RASA stands for Rowe-Ackermann-Schmidt Astrograph - Dave Rowe and Mark Ackermann are renowned optical instrument designers. Together, they hold numerous patents on their inventions. The RASA astrograph combines their expertise and experience.
The Astrograph RASA 36 features the following:
- A corrected image circle of 60 millimetres for needle-sharp stars right to the farthest corners of the largest sensors available. The usable image circle is as large as 70 millimetres.
- The four-element lens group uses extra-low dispersion (ED) glass for imaging without chromatic aberration, coma and field curvature (spot size: < 6.3 μm RMS across FOV). The usable spectral range is between 400 and 900 nanometres, so that the sensitivity of the sensors can also be used in the near infrared up to 900 nanometres.
- The newly designed Ultra-Stable Focus System (USFS) minimises focus drift or other unwanted movements of the primary mirror and enables easy and stable focusing.
- With the included adapter, this results in a back focus of 55 millimetres which is ideal for DSLR cameras, as shown in the application example.
- The two pre-installed wide prism rails (Losmandy standard) allow mounting on large mounts and further adaptation of accessories, for example on a telescope for visual inspection.
The new version V2 is equipped with the Ultra Stable Focus System (USFS). It is focused by moving the primary mirror. So that there is no image shifting and tilting, focussing is controlled via a precise linear ball bearing system.
Focussing can be achieved using the Celestron focussing motor.
It not only matters which telescope you buy but also where you buy it. Our additional services:
- We are a leading telescope dealer and know the devices we sell. Our customer service team will gladly help you after your purchase if you have problems with assembly or operation.
- We provide a copy of the 80-page Telescope ABC beginners handbook with every telescope.
