View Full Version : Follow Focus with C-mount

11-06-2009, 05:12 PM
Dear All,

I looked through the web and could not find any info on follow focusing with c-mount lens attached to GH1.

Actually, I have already ordered D-Focus with gears of all sizes. But i'm not very much sure that FF can be easily archived with those lenses.

Does the front part of the lens move while focusing? If anybody has any experience, that would be great.
Particularly I'm interested in this lens:
http://cgi.ebay.com/COSMICAR-12-5MM-F-1-4-C-MOUNT-LENS-1-FORMAT_W0QQitemZ120489049940QQcmdZViewItemQQptZCam era_Lenses?hash=item1c0db4ff54#shId

Images of rig are welcome :)

Best regards,

11-06-2009, 11:10 PM
Unless the focus ring travels longitudinally as you turn it you should be fine.

11-07-2009, 02:43 AM
Unless the focus ring travels longitudinally as you turn it you should be fine.

Ok. Then the question is which cheap fast inexpensive C-mount lenses have focus ring, which doesn't travel longitudinally? :)

Personally, I have only 35mm still photography lenses + medium format and have absolutely no clue about c-mount.

But I suppose this one, for example, will not work:
http://cgi.ebay.com/Wollensak-Raptar-50mm-F1-9-C-mount-lens-G1-EP1-camera_W0QQitemZ280418483947QQcmdZViewItemQQptZAU_ FILM_CAMERAS?hash=item414a3e7eeb

And just a side question:
which c-mount to 4/3 adapter you use?
I found couple on e-bay:
1) http://cgi.ebay.com/C-Mount-to-Micro-4-3-Adapter-for-G1-GH1-Olympus-EP-1_W0QQitemZ250515262075QQcmdZViewItemQQptZLens_Acc essories?hash=item3a53df8a7b
2) http://cgi.ebay.com/16mm-C-Mount-lens-to-E-P1-G1-GH1-micro-4-3-adapter-Cap_W0QQitemZ370273896882QQcmdZViewItemQQptZLens_A ccessories?hash=item56360b49b2
3) http://cgi.ebay.com/C-Mount-to-Micro-4-3-m4-3-m43-adapter-G1-GH1-GF1-E-P1_W0QQitemZ250526200289QQcmdZViewItemQQptZLens_Ac cessories?hash=item3a548671e1

I got a reply from e-bay seller saying that focus ring DOES travel longitudinally.
I propose everybody, who use c-mount participate and make a list to know which lenses will work and which won't:

c-mout ---------------------- FF
Cosmicar 12.5 f/1.4 -------- no

11-07-2009, 09:13 AM
I haven't used any C-Mount lenses, so I can't be of any more assistance, sorry.