Dave,
The P30 and P30+ aren't recommended on technical cameras that have tilts and shifts. With any lens wider than a 47mm the light can strike the microlenses at a sharp angle and not give a favorable result. I might suggest either a P45/P45+ or a P65+.
Chris Lawery
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chris@captureintegration.com
Capture Integration, Phase One Dealer of the Year
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I've used the contax 35mm on the p21+, p30, p30+ and seen no more issues than any other digital camera, in regards to fringing, ca, etc. Even wide open at 3.5.
I have seen some blue fringing on strong backlight, but that's not the wide lens, as I've seen blue or purple fringing on almost every lense and every digital camera with strong backlight from time to time. Film would even do it under certain circumstances, though I see no more fringing or ca on the micro lensed phase cameras than I did from the Aptus 22.
I don't use a technical camera, but even with the old Boris tilt shift I never saw anything that different, other than the lens has a nice softness to it.
A lot of this just comes from the way we now shoot. In the film days if you shot a subject against a strong backlit scene you would try very hard to match the light of the subject to the background, knowing that any loss of background detail would be difficult to replace. The photographer also shot more carefully, because the polaroid proof didn't give enough real information to know if you were balanced correctly.
Regardless of how we balance the light, now we usually always move the background around in some ways, or even replace it all together, so consequently we now shoot with stronger backlight than we did in the film days hence more of a chance of fringing around the subject.
Maybe the slightly tigheter crop of a p21/p30 helps with wide angles, but most people forget that up until the p65, medium format digital sensors were not really 1.1 vs 1.3 crops on a 645 frame, they were approx. 1.14 vs. 1.24, which is not that great of a difference.
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