Tamron 17-50mm f/2.8 focusing problem
Hi, I just got a brand new Tamron 17-50mm f/2.8 XR DI-II LD for my K-x, (got it from TheCameraBox), was very excited until ran a series of improvized tests against my 18-55 Pentax kit lens. At first, I thought smth is wrong with my tests, as the kit lens was consistently sharper on some of the shots. I made tests more and more controlled, until I pinpointed the problem.
For some reason, in 100% of trials, my k-x + tammy lens auto-focuses slightly ahead of the subject starting exactly at 5.6. So, 5.0 focal point is dead on target, 5.6 is ~2% ahead, which obviously makes it blurred. I see the effect at all focal lengths, but its most destructive at longer end, obviously.
Any ideas? Would this be a lens' fault, or is it the k-x/firmware?
Thanks,
Greg
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