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Old December 27th, 2007, 07:42 AM
Bart_van_der_Wolf Bart_van_der_Wolf is offline
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Quote:
Originally Posted by Nicolas Claris View Post
Once you realize that the tests should be run wide open, it becomes really easy…
Yes, sorry for not making that more clear. LifeView should be used with aperture wide open (most shallow DOF). So, how did you like using the test target? Was it easy enough to see the moiré? Should I add some detail to allow inspection of an actual shot, although there's no real need to shoot anything?

Quote:
So, thanks Bart (and Canon…)

My Sigma 12-24 comes back to life… micro adjustement settings = +15 !!! (and I thought it was a good copy!)
It doesn't mean the lens is bad or anything, just that the combined calibration of body and lens produces consistent front or back-focused results, which can now be self-adjusted on some models.

I know what you mean with coming back to life, my 200mm f/2.8 required +19, the other lenses much less. From average to pin sharp, without the need to inspect focus bracketed sequences or even take a single shot, what a difference. I've found the adjustment in actual shooting conditions to bring about a much better average focus accuracy. There can still be slight differences due to subject contrast on 3D subjects, but the average is better.

It can also reveal a bit of a desillusion on some zoom lenses, pinsharp on one end of the range, and soft/defocused on the other. An alternative would be to use a sort of average adjustment, or just optimize at the long end, and MF on the short end. I'm not sure if CPS lens calibration will affect differences between short and long focal lengths.

Well, it saved me from having to let CPS calibrate the lot.

Bart
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