- Works with objectives between 300 - 800mm focal length via adjustable lens barrel
- Fully covers 35mm full format sensors
- M57 male on objective side
- M57 female on camera side
- Back focus : 55mm
- 7108 - 7923 - 5005 - [Canon DSLR]
- 7108 - 7923 - [M49.8-STL AD] - [SBIG STL camera]
7000 may be used in place of 7923
but a 5mm
adjustment is necessary (lens barrel must be pushed in 5mm)
Each index mark is optimized to cover a 35mm full format sensor.
For sensors smaller than APS-C sized sensors,
the lens barrel should be extended out around 1.5mm.