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X ray lenses those Exotic 0.75 and 0.95s KOWA etc
Old 12-27-2011   #1
bene
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X ray lenses those Exotic 0.75 and 0.95s KOWA etc

Hi all I am quite the night photographer and been looking to push the limits.... dark streets emotive looks...

I am keen on the KOWA 42mm f0.75 on sony nex is it possible to build the focus helicod and mount? I need infinity and at least 2 m

Would the lens cover the sensor?

Are there alternatives?

I have the vc 50 1.1 and 35 1.2
So the only logical choice is something even faster..
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Old 12-28-2011   #2
bowieknife
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Hi, I have the Rodenstock TV Heligon, 50mm f/0.75.
Focus distance is about 1 foot.
Can't bring the back element of the lens close enough to the sensor for "infinity". Not even with a Nex.
Attention. by modifying the lens so it would approach infinity, you risk breaking the shutter !
Be very careful !
Possibly a Nikon 1 or Pentax Q is the way to go (=shorter register distance).
Still, those special lenses have too much "glow" to be really useful.
If you can spend some money, try to find a Schneider Xenon 50mm f/0.95 in C-mount, that lens gives excellent results, is focusable and has aperture blades as a propper lens should.
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Old 12-28-2011   #3
bene
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@ bowieknife: Thanks! probably have to ask around who does such modification I aint able to do such things , what about cannon 0.95 how would does it compare? to the xenon?
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Old 12-28-2011   #4
Ezzie
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I saw, just yesterday a picture on Flickr of a 55mm Kowa industrial lens on an m43 Panasonic. It had both a helicoid, and aperture adjustment. The owner had bought it ready adapted. The down side was that these adaptions had changed the effective focal length to 90mm, making it a 180mm on an m43 camera, 135mm on an APSC camera.

EDIT: found it http://www.flickr.com/photos/hhackba...n/photostream/
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Old 12-28-2011   #5
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Yup I found the ebayer who sells this but the thing with the VC 50 1.1 being quite decent it doesnt make sense to get it the ebay has it in Nex mount
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Old 12-29-2011   #6
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Hi, just want to add that some mods to make those lenses work on a DSLR , Nex or MFT not only augment the focal length, but also lower the effective speed of the lens ( these mods work like teleconverters ), so I don't see the point....
While I never owned the Canon 0.95, it seems to be a good choice, prices are still reasonable compared to superfast Leica Noctiluxes.
Be aware that DOF becomes extremely thin at such apertures, a high percentage of shots are crap due to focus errors resp. subject movement.
My Schneider Xenon 50mm from 1967 works fine on a Nex, but would vignette somewhat on a FF camera.
Got mine for ca $1000, but have seen auctions going up to $2500 +
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Old 01-11-2012   #7
AJS Lamb
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"Are there alternatives?"

A tripod. Don't wish to sound facetious but a tripod allows you to use your current lenses without worrying about the need for speed.
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