OTA · 2024–
Askar 91F
Key specifications
| Aperture | 91 mm |
|---|---|
| Focal length | 609 mm |
| Focal ratio | f/6.7 |
| Optical design | Quadruplet APO |
| Weight | 3.92 kg |
All specifications
| Focuser type | 3" dual-speed rack & pinion, 1:10, 360 rotator |
|---|---|
| Tube length | 513 mm |
| Dovetail | Vixen |
About
91mm f/6.7 self-flattening quadruplet astrograph (3+1) with one ED element. 609mm focal length over a 44mm full-frame flat field, no separate flattener required; CNC tube with internal baffling.