Samyang 135mm f/2.0 ED and 85mm f/1.5 UMC VDSLR for astronomy with EAF

Adapting Samyang135mm f/2.0 ED and 85mm f/1.5 IF UMC VDSLR lens for astronomy with EAF or OnStep focuser

EAF holder is compatible for SCT and Newton telescope.

For fine manual focus ring available too.

Optional rings for old Carl Zeiss Jena Sonnar 180mm F/2.8 lens available only for manual focus.

OpenSCAD source code on GitHub

###BOM
1x Samynag 135mm f/2.0 ED (Canon, Pentax, Nikon, Sony ....) or 85mm f/1.5 UMC VDSLR lens
1x ZWO EAF
1x ZWO ASiair (Pro)
1x GT2 Timing pulley 20Teeth/Bore 5mm
1x ~400mm GT2 Open Timing Synchronous Belt 6mm (for Samyang 135mm)
1x 136mm GT2 Closed Loop Timing Synchronous Belt 6mm (for Samyang 85mm)
10x M4x20mm imbus screew
4x M4x25mm imbus screew
2x M4x20mm Hex Head Screws
12x M4 nuts
3x M5x30 imbus screew
1x M4 nuts
10x M3x25mm screew
13x M3 nuts
2x Ball Bearing MR115 (5x11x4mm)
1x 1/4" - 20 UNC photo screw

#####Optional for OnStep focuser
1x Nema17 Stepper motor 17HS15-1704S
1x GT2 Timing pulley 16Teeth/Bore 5mm
4x M3x10mm imbus screew
4x Self Tapping Screw 2x6
1x RJ45 - PCB on EasyEDA

Update

• 2021-01-01 Add beld tensioner
• 2021-01-27 Add support for Samyang 85mm f/1.5 UMC VDSLR and some improved