Helicoid focuser – M42/C-mount to Micro 4/3rds

This helicoid focuser comes as two parts: M42 to M42 17-31mm helicoid, and the short M42 (c-mount) to Micro 4/3rds adapter, which has 25.5mm and M42 female threads. This allows for use of 25.5mm filters, which can come in handy.

M42 (c-mount) to Micro 4/3rds helicoid
M42 (c-mount) to Micro 4/3rds helicoid
Fully extended
Fully extended

Cost: about £30 from Hong Kong

M42 (c-mount) to Micro 4/3rds adapter
M42 (c-mount) to Micro 4/3rds adapter
Weight of 17-31mm M42 helicoid
Weight of 17-31mm M42 helicoid
Weight of helicoid with M42 (c-mount) to Micro 4/3rds adapter
Weight of helicoid with M42 (c-mount) to Micro 4/3rds adapter

Weight of the M42 (c-mount) to Micro 4/3rds adapter is 22.9g

17-31mm helicoid fully retracted
17-31mm helicoid fully retracted
17-31mm helicoid fully extended
17-31mm helicoid fully extended
Helicoid + adapter fully retracted
Helicoid + adapter fully retracted
Helicoid + adapter fully extended
Helicoid + adapter fully extended

Thickness of the M42 (c-mount) to Micro 4/3rds adapter is 5.65mm. It extends by 14.09mm in total.

Impression:

This adapter is very useful and fairly light, especially the fact that it can also be used with a 25.5mm filter (which fits in the c-mount female threads). However, the adapter with helicoid is too thick to allow for infinity focus with my 35mm F3.5 enlarger lenses. There is only a tiny amount of play with this adapter. I like this helicoid focuser and use it very often. Definitely worth getting.

Boon