I am not sure but in certain bright condition my lens seems to have trouble finding focus lock. it searches then when I try it again it will lock. I have noticed some of my images are dull and lack sharpness. Otheres are fine so I am not sure if I have a problem. I checked to make sure I had not changed settings. Has anyone else had problem with focusing in certain light conditions. This is with the 18-70 lens.
The autofocus needs contrast to find the subject. What are you shooting and have you tried manual focus? Or focusing on something else the same distance away, locking and recomposing?
Thanks Larry I had guessed that was the problem. I also notice in low light situation some subjects are hard to focus. I am not afraid to manual focus. I am very used to doing that. I have noticed if I zoom out or in on my lens when it is not focusing that helps find it. I also focus on something else and that seems to work. It just seems to be happening more often then before. Monte.
Monte, try using just the center focusing sensor rather than the multipoint. Focus, hold down the shutter release 1/2 way down to lock focus and recompose.
I believe some zooms are not parfocal these days and will therefore change focus when you zoom in or out. So frame the shot and then focus.
This is a good article that covers the focusing modes on the D200. Hope it helps.