Hello
Has anyone has done some experiments adding some spacing between g-claronīs lens groups and checked for improved shapness?
just to know if itīs worth the ride...
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Hello
Has anyone has done some experiments adding some spacing between g-claronīs lens groups and checked for improved shapness?
just to know if itīs worth the ride...
Mine came with a brass spacer. I've not experimented with it further because it's sharp as is with the spacer in place. I figured someone before me knew more about the need for it than I did, and I left well enough alone. It sits in front of the rear element.
Peter Gomena
Do you have an optical bench with the skill and experience to use it? if "no", just trust Schneider.:)Quote:
Originally Posted by ruilourosa
hello
i asked beacause i heard that incresed spacing could benefit infinity sharpness at wide apertures!
It might. I've heard it was decreased spacing, though. It can't hurt to experiment, as long as you don't damage any threads or lose any spacers that might already be there.Quote:
Originally Posted by ruilourosa
Clarons are very sharp lenses and you'll be hard put to see any difference with standard film holders.
If you have a way to check the corners for focus, then just unscrew the lens and test. If you know the pitch of the threads, you know how far out the lens comes with each revolution. I did some film tests with my Angulon 210 at various front/rear cell spacing. but went back to the factory specs. With that lens I it appeared that the focal "plane" was not so much a dish shape but more like a sinusoidal pattern of concentric rings like a drop of water in a puddle. As I got the very far corners to match the center, other areas of altered near or far focus would crop up at intermediate distances from the center. The factory spacing gave the best compromise.
At f/9, my 305 G-Claron does not have a particularly wide aperture at all. It also is not at its sharpest wide-open, but if that's due to cell spacing or to lens aberrations characteristic of the lens design, I have no idea. I do know that at f/16, it becomes very sharp.
I once used it wide-open on my 4x5 to photograph distant fireworks. Focused at infinity, it was able to resolve the fireworks adequately for a nice 11x14-inch print. I can think of no other time I've used it at f/9.
Peter Gomena
Does anyone know if the spacing is the same for factory mounted shutter and barrel lenses? I see that Red Dot Artars did vary the spacing for shutter lenses. See http://www.cameraeccentric.com/html/...hneider_4.html You have to go to the Red Dot Artar page to see what I'm referring to.
the spacing is exactly the same, barrel or shutter (compur 1) measured with a digital precision vernier! maybe someone with a digital adaptor (i am building one!!!) or digital back is willing to do some testing...
You'll need to check the corners, as well.Quote:
Originally Posted by ruilourosa