Originally posted by ChopperCharles Check that, it's not just the tammy. I've been going back through my lenses, and my 18-55 front focuses by the same 4mm, and my Sigma 28-105 UC-II front focuses by 6mm. My Vivitar f1.7 50mm manual, the focus confirmation also goes off at 4mm front-focused.
HOWEVER, my Tokina 35-70mm and my 55-300mm DAL are perfectly dialed in, and the SMC-F 35-70 is close, maybe 2mm at most front-focused.
Soooo, do I have a bad Kx then?
Charles.
I have the same issue with my K-x, anyone with more than a few lenses is going to strike the same problem. What I do to solve it is adjust the debug AF amount so that as many lenses as possible at least have the focus point within the DOF, even if some are slightly FF and some slightly BF. You just want to ensure that what you focus on with each lens ends up within the DOF.
For me I have 1 perhaps 2 which can't be adjusted to achieve this when they are wide open, not without throwing out too many others lenses. For those lenses I know I need to stop down or purposely fudge my focus point to achieve an in focus image.
My advice then to to adjust to compensate for a little bit of FF, but not enough to ruin your 55-300.
This is one good reason to buy a K7/K5/K20.