Takahashi ε-180ED
Optical design Hyperbolical Newton
Effective aperture 180mm
Primary mirror diameter 190mm
Secondary mirror (minor axis) 80mm
Focal length 500mm
Focal ratio F/2.8
Resolution 0.64"
Limiting magnitude (visual) 13.0
Light grasp 661x
Image circle 44mm (60% not vignetted)
Back focus (BFL) 56mm (from the end of the corrector)
Photographic assembly M54mm female on the corrector (for wide T-mount)
Tube length 570mm
Tube diameter 232mm
Tube weight 10.7kg