C-Mount lens: the hunt begins anew

psoetio · Mar 6, 2011

I had lost track of this thread; happy to find it again. Has anyone experimented with using wide angle converters on zooms meant for 1/2" or 2/3" sensors? In theory you could have a fast but also nice and wide zoom without vignetting that way..

seb33 · Mar 6, 2011

Modified Cosmicar 12.5mm 1:1.4 + 40.5MM to 43mm Step up ring + Polaroid variable ND o

Modified Cosmicar 12.5mm 1:1.4 + 40.5MM to 43mm Step up ring + Polaroid variable ND o

Modified Cosmicar 12.5mm 1:1.4 + 40.5MM to 43mm Step up ring + Polaroid variable ND on GH2

Here's Flick'r link of the configuration
http://www.flickr.com/photos/43243778@N04/sets/72157626085815881/
http://www.flickr.com/photos/43243778@N04/sets/72157626085853993/

This is a film with my new C-mount Cosmicar 12.5mm 1:1.4, modified to fit on the C-mount to micro 4/3 adapter (see pictures below).
This lens is less sharp than the Lumix 14mm 2.8, but faster. It's vignetting a little, not a lot for this focale. It's not protubing so no problems with the GH2.
I've put a 40.5mm to 43mm step up ring to adapt a 25$ variable Polaroid ND filter (sorry the film credit is wrong)
But with this the vignetting is bigger, that's why I have to zoom and crop the image for this movie (from 100% to 130%).
I also bought a Cosmicar 6mm 1:1.2, wich seems to be sharper, I will use it with the GH2 crop function, it's being modified, I'm having it next week, tests soon.

GH2 24P
C-mount Cosmicar 12.5mm 1:1.4 always fully opened
160 asa
shutter 1/50
Step up ring 40.5mm to 43mm
Polaroid 43mm ND filter

Music : Elusive "My friend" from "Pressure Drop"
Duration : 2mn11sec

I'had also shot the carnaval one year ago with the Angenieux C-mount 25mm 0.95, link here :
vimeo.com/10057438
link for another Computar lens on EOSHD :
eoshd.com/content/512-Is-this-the-scariest-GH2-lens-in-the-world-Computar-8mm-F1.3

Andrew Reid · Mar 10, 2011

Good work Seb. Just bear in mind - with the 6mm Pentax, it needs to be modified to get infinity focus, otherwise it's only good as a macro lens. Modifying it requires a specialist - can be as cheap as $20 but you need to find the right guy.

seb33 · Mar 10, 2011

Andrew Reid said:
Good work Seb. Just bear in mind - with the 6mm Pentax, it needs to be modified to get infinity focus, otherwise it's only good as a macro lens. Modifying it requires a specialist - can be as cheap as $20 but you need to find the right guy.

You're right Andrew, I've done it once one year ago by myself, it's was a disaster ! But I'm not a good handyman

seb33 · Mar 10, 2011

For those who did not see this mod, here's a C-mount modified Pentax 6mm 1:1.2 with two tests :

Apefos Adapter · Apr 21, 2011

eyeBOX · Apr 22, 2011

http://cgi.ebay.com/NAVITAR-1-3-75m...19658450?pt=Camera_Lenses&hash=item41563c2cd2

Does anyone have any experience with this lens on the gh2? What type of adapter did you use? Will the kipon m43 / cmount adapter work? Videos?

Thanks in advance..

seb33 · Apr 26, 2011

GH2 gets WIDE from 6mm to 3.5mm !!!!!

This is a movie shot with three lenses, from 6mm to 3.5mm, which is 15mm to 9mm for micro 4/3 sensor (24X36 : 31mm to 18mm). 1st part with the 6mm (more info: http://vimeo.com/20766631), some shot with polaroid variable ND filter. Second part, same lens but with a Pixco 0.45X lens converter, found for 16€ on ebay, it's 40.5mm screw mount filter size lens is perfect for the Pentax. The third part is shot with a new lens I've found on Ebay for 46€, a C-mount Rainbow 3.5mm 1.6, perfect for the crop function ! It's very wide, little fish eye effect, but I have a little focus problem with my copy, so I have to closed the aperture, but not too much because it seems I have problem of intern dirts, that can be viewed in more closed apertures.
I like this 3.5mm Rainbow C-mount lens, it's fun and very wide. I hope you'll enjoy the shots.

C-mount Pentax 6mm 1.2 modified http://tinyurl.com/3muqwbe
C-mount Rainbow 3.5mm 1.6 http://tinyurl.com/65v4tjc
Picko wide angle lens converter 0.45X http://tinyurl.com/3fdvw48

GH2 with crop mode 1:1
No CC
Edited on Premiere CS5

Music : JUSTICE "Genesis"

samjovanou · Jun 9, 2011

Oh hey, after reading through this entire thread i thought i'd add a little bit to the fun.
I recently got my hands on a Fujita 38mm f1.4 cine lens.
Size Comparison - http://bit.ly/kvPGzy
The Mount: http://bit.ly/jUJVl7
Couple more:
http://bit.ly/lvXuFo
http://bit.ly/lWnkTT
It covers the whole m4/3 frame and seems to focus fine, haven't had a chance to fiddle with it yet to make sure and check it's quality, but i'll post up some example footage soon from my G2 so we can all see this beauty in action.
I couldn't find a single snippet of information on the internet for this badboy, it's VERY nice to handle though, weighs almost as much as the G2 without its battery!
Is there maybe some information someone can find about this lens out there?
Anyways i'll update you all soon with some video action

ed_lee83 · Jun 10, 2011

samjovanou said:
Oh hey, after reading through this entire thread i thought i'd add a little bit to the fun.
I recently got my hands on a Fujita 38mm f1.4 cine lens.

Covers the whole sensor? What camera was it designed for?

Meanwhile I just did this test with a modified Fujinon 12.5-75mm f1.2 that is also up for sale on eBay (link in the YouTube page):

Sam Scoggins · Jun 14, 2011

My favorite c mount on the GH2 - 2 inch Dallmeyer Triple Anastigmat f/2.9

moxrox · Jun 15, 2011

Interesting c-mount lenses, but not sure about the price...

http://www.lensation.de/en/shop.html?page=shop.browse&category_id=15

mcbob · Jun 18, 2011

Kern Switar 16/1.8

Winds up as easily the smallest, most compact 83/1.8 I've ever owned.

http://vimeo.com/25265410

C-Mount lens: the hunt begins anew

psoetio

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Andrew Reid

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Apefos Adapter

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eyeBOX

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