I have an older TamronrnAF 28-200 1:3.8-5.6 and obviously cannot use it with my Nikon D70. Thernproblem is that it works fine at a focal length of 28mm, but the more Irnzoom out the more problems I get focusing on things, meaning that it's not possible to get a sharp view at 200mm. The lens however seems to be working fine if I focus on things that are quite near, even at 200mm.
I already checked whether this could be an AF problem switching my camera to the 'M' mode, but that didn't have any effect.
I know it might be quite obvious to you what the problem is, but please explain it to me. Any comments much appreciated!