With an astrograph, you have a Newtonian telescope that is optimised for astrophotography: fast, corrected optics with a temperature-stable tube and a solid focuser.
Newtonian astrographs from ASA meet the high demands of discerning astrophotographers:
- The carbon fibre construction of the tubes results in high rigidity, low weight and extremely low thermal expansion. This keeps the focus stable during long exposures. The tubes are lined with velvet to prevent stray light. A fan is mounted on the rear to ensure faster temperature adjustment before use.
- The ASA Astrographs have a very fast aperture ratio. This allows you to achieve a favourable signal-to-noise ratio in a much shorter time. Thanks to the correction optics used, sky images are rendered cleanly right into the corners, even when using large camera sensors: Perfect correction over large fields of view!
- The precision focuser is motorised and operated by a stepper motor: perfect and torsion-free operation thanks to six bearings!
The Newtonian astrographs feature parabolic primary mirrors made of borosilicate glass from SCHOTT (Suprax) with P/V < 1/7 lambda wave and 97% mirror coating and are supplied with a Zygo interferogram.
Your advantages at a glance:
- Fast aperture ratio, therefore extremely short exposure times
- Use of the world's best correctors
- Lightweight construction with high-quality CFRP carbon fibre
- Extremely accurate and robust focuser (including ASCOM-compatible software)
- Very precise manufacturing tolerances to achieve a stable system
Included in delivery:
- Focuser including motor, software and cable
- Main mirror fan with cable (5V-15V)
- tube clamps
- Laser collimator
- Sturdy transport case made of birch plywood with steel ball corners, aluminium profiles, flip handles and butterfly locks.
This version of the 20N Astrograph from ASA comes with a 2" Barlow corrector.
- Corrected field of view: 30 mm
- Back focus: 124.55 mm
The corrector changes the characteristics of the OTA as follows:
- Focal length: 3420 mm
- Aperture ratio: f/6.84
Camera adaptor: Please be sure to specify your camera when ordering. You will then receive the appropriate adaptor with your order.
