The TS Optics PHOTOLINE 0.79x reducer / corrector has been designed for astrophotography through APO refractor telescopes. It makes the system faster and corrects for the field curvature even with full size sensors. It does not need the extreme back focus of the Riccardi corrector. It is suitable for all models with focusers from 2.5" and connects to them via M68 thread or 3" barrel.
Back Focus - distances from the M48 thread to the camera sensor depends on the focal length of the telescope:
- Focal Length to 350 mm: 70 mm
- Focal Length to 420 mm: 65 mm
- Focal Length 450-500 mm: 61 mm
- Focal Length 510-600 mm: 58 mm
- Focal Length 610-700 mm: 57 mm
- Focal Length 710-790 mm: 56 mm
- Focal Length from 800 mm: 55 mm
