Some real world shots from my 16-50, is this a good copy? Serial number is 9024618...
I also just did a BF/FF issue test awhile ago, and at 50mm, it sightly back focuses. AF at 16mm though suffers from moderate BF... just like the 50-135, I'll just make it a habit to focus while zoomed in first, then zoom out to compose. Is this problem evident with the K20D? Or only with the K10D?
I also did a quick newspaper test (no tripod, not sure if its parallel), and it seems ok. With corner softness (as expected from a zoom), but not much. Center is sharp. Will do a more "scientific" newspaper test later though.
In all I think I got a good copy cept for slight back focusing. IQ is very much comparable with my 50-135 when sharp, and suffers from the same AF issues as its big brother (soft focus at wide end, have to focus zoomed in). Should I exchange my copy?
to add: with the K100D, it is just perfect. Is SDM really this inaccurate? Or should I learn to live with it?