focus gears for Leica M photo lenses?

[Ryan Chernin]

Hey all,

Has anybody had success with fitting a custom focus gear to Leica M photo lenses? That finger adjustment knob looks like it'd be a problem.

Thanks!

 

[Les Hillis]

I've used gears similar (but not the same as) these - https://www.ebay.com.au/itm/12304410...cAAOSw8oxaugh7

They just need to have the prong that hits the finger adjustment knob cut down to fit.

The Leica-M mount lenses can get pretty small in diameter though (about 160mm circumference, 50mm diameter), so you'd have to make sure the prongs can reach the lens. You might also have to cut the prongs down in width too where they contact the lens, as the width of the focus ring can be small too.

I've also used these, and they could work if you pack out the space on the lens around the adjustment knob then attach the ring around it - https://www.bhphotovideo.com/c/produ...ocus_gear.html

Depending on the reach of your particular follow-focus unit, you might also have to pad out the gears so they can reach the follow-focus. You can do that using multiple layers of the focus gears in segments, remembering those Leica-M mount lenses probably only have 120 or so degrees of rotation so it's not like you'll be using the entire circumference of the focus gear to actually focus with.

I've found using gears set up around the finger adjustment knob like that to be secure enough in actual use, but handling the lenses takes extra care so as not to dislodge the focus rings once they've been attached.

 

[Alex Cristescu]

I've talked to Duclos lenses in the past about this and they said they can do focus gears with M mount lenses that have the notch. I would get in touch with them and see what they say. Keep us posted, I actually use M mount glass as well and am finishing up my collection before I get them sent off to be modded. Good luck.