[frank]

[quote name='Klaus' timestamp='1326810925' post='14963']

1. a softer edge will remain comparatively softer regardless of the sharpening. Please note that this tests is for the center only. If there's an issue here it will be amplified in one (or more) border zone.



2. this is a bit surprising. The exposure should remain roughly constant. Have you used spot metering ? You shouldn't treally try to reach 100% white. A light gray tone for the white field is fine.



I'd say that the decentering is not extreme in your sample. Nikon may still respond that this is within factory limits. Remember that no lens is 100% centered anyway. If you have an issue in the field it should be taken care of (I didn't follow the whole thread so maybe you've mentioned this already).

[/quote]



Thank you, Klaus. If the problem is not serious then I will not bother to send the lens to Nikon. I may retest the problem tomorrow, with the metering method you suggested. I am just curious why the "blur" style changes after rotation and why the rotation makes the decentering look more obvious.



I started to think decentering when I took the following shot (the lens is not rotated, but shifted upward by a moderate amount), where I noticed that the sharpness of the brick wall fades gradually toward the right end of the image. But later I thought that it could just be the gradual fading of the DoF. The aperture that I used was f8.







Here is an image taken with the lens rotated so that I can shift vertically in the portrait style. The amount of shift was about 10mm, if I remember it correctly. The used aperture was f5.6.







Best regards,

Frank