Nikon F60 Problem...

Take some photos (with different lenses if at all possible)... and examine
them... make sure you're camera and tripod are properly aligned of course... a
lot of viewfinders have distortion, so looking through one to judge may not be
the best idea; even my F5 gives me hell when I do that. If your shots come our
fine, you're fine... if it only comes out bad with a certain lens, it's the
lens. If it all comes out bad, it's your camera, send it in. Make sure your
alignment is 100% spot on though! And also remember that most lenses have
noticeable barrel and pincushion distortion, which can cause straight lines near
the edges of the frame to become concave or convex, depending on how you look at
it.