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C-mount Cine lenses on G1
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PostPosted: Tue Jan 06, 2009 11:45 pm    Post subject: C-mount Cine lenses on G1 Reply with quote

http://www.flickr.com/photos/cinegon/

I don't know if this was posted before -

This guy has tried Cooke, Dallmeyer, Kinoptik, etc. C-mount lenses on his G1. It looks like the longer focal lengths have coverage for 4/3, but short FL's maybe not.


PostPosted: Wed Jan 07, 2009 12:10 am    Post subject: Reply with quote

Shocked Shocked

wow -- very nice indeed ..

tf


PostPosted: Wed Jan 07, 2009 12:13 am    Post subject: Reply with quote

Good advertise for micro 4/3 we should run to purchase cine lenses before too late Wink


PostPosted: Wed Jan 07, 2009 12:59 am    Post subject: Reply with quote

I have made some tests with my 17-70 2,4 SOM Berthiot c-mount.
I disasembled the rear to get some focus with my Pentax K10D. Then I compared sensorsizes and the pictures I got.
Funny how different the lens coverage is with different c-mount lenses.

Here is the result:


One of the pictures taken on the Pentax K10D.


/Jan


PostPosted: Wed Jan 07, 2009 1:02 am    Post subject: Reply with quote

Thanks for all of you for samples!


PostPosted: Wed Jan 07, 2009 1:51 am    Post subject: Reply with quote

A small clarification to my earlier post with sensor sizes. The Panasonic G1 has a standard 4/3 sensor size, hence the inner box.
This lens will therefore, sadly, be useless on the G1. Crying or Very sad

Probably the primes have a greater coverage as seen in the link provided by luisalegria.

Off topic: I want a really small camera with interchangable lenses, smaller registration distance and a smaller sensor that can mount all the 8mm cine lenses. How cute wouldn't that be. Very Happy

/Jan


PostPosted: Wed Jan 07, 2009 4:05 am    Post subject: Reply with quote

Hi Jan,

You may want to try the lens at different focal lengths - the coverage may change. Usually I think the coverage at longer FL is greater than at short FL.


PostPosted: Wed Jan 07, 2009 9:36 am    Post subject: Reply with quote

Luisalegria: The shot above is taken at 70mm the longest focal length. I could not go to 17 mm due to the object hitting the lens but at around 25-30mm it looks like this.



Basically the same coverage.

First I thought it was the actual mount but in these experiments the mount is removed completely.

I might have shifted the rear optical block forward, closer to the aparture. I had to do that to get a focusing distance at all. Do you think that could have an impact?

These cine-zooms are really cool. I have heard of zooming with you feet, but here you can actually zoom with a stick. Very Happy

/Jan


PostPosted: Wed Jan 07, 2009 9:54 am    Post subject: Reply with quote

Click here to see on Ebay

I think it's not cover full frame of G1


PostPosted: Wed Jan 07, 2009 11:12 am    Post subject: Reply with quote

I'm buying a cine Canon 11-110 1:1.6 macro and P6 mount 80/2.8(don't know the brand) for 30Euros, can buy a G1 in the summer for this cine lens but I'm waiting them to support video first Smile


PostPosted: Thu Jan 08, 2009 1:28 am    Post subject: Reply with quote

It's impressive that so many C-mount lenses seem to cover such a wide area. The largest area any C-mount lens would ever have had to cover would have been 16mm film, which has in image size of 10.4x7.5mm, much smaller than the 18x13.5mm of the 4/3 system. Unless, of course, there were actually some TV cameras or something that used sensor tubes with an equivalent area to a 4/3 sensor, in which case this begins to make more sense.


PostPosted: Thu Jan 08, 2009 2:07 am    Post subject: Reply with quote

Not all C-mount lenses were designed for 16mm - quite a few longer lenses share everything but the actual mount with the 35mm version.

And on some, the coverage restriction is only due to the narrow C mount neck or a baffle inside the same, so that they could cover more in another mount.

Sevo