Nikkor 35-70mm 2.8 Hunting

I have a F100 Nikon Film Body and just purchased a Nikkon AF 35-70mm 2.8 lens for it. The lens looks to be in great shape and will quickly automatically focus from 35mm to 50mm. However, at 70mm the lens just "hunts" and won't "snap" into focus. Is this a lens problem? Comments?
Thanks

boodalu said:

I have a F100 Nikon Film Body and just purchased a Nikkon AF 35-70mm 2.8 lens for it. The lens looks to be in great shape and will quickly automatically focus from 35mm to 50mm. However, at 70mm the lens just "hunts" and won't "snap" into focus. Is this a lens problem? Comments?
Thanks

Click to expand...

Do you think it may be one of the camera's sensors??? I had one of these lenses, great lens. Seems odd. I would try it on another body. This is the push / pull zoom model??
I like these older lenses because I'm done replacing lens motors! The new Nikon plastic wonder lenses don't hold my attention. I know that the lens does tell the body what focal length it's at for the dopey zoom flash.
Try switching which sensor is active on the autofocus???
Clean contacts?

To auto focus good contrast in the subject matter is important. Focusing on the edge of a sheet of paper is easy, focusing on the center of a blank sheet of paper is near impossible.

Try an easy target.

Also, these systems generally want clean vertical lines in the subject.
And no confusing arrays of small features, like windows on an office building in the distance.

These issues are discussed in the camera manual.

- Leigh

I am using very contrasting targets. Will try on another body. As I previously mentioned any thing under 50 mm it works perfectly.
PS. It is a push / pull lens.

To close the loop on this....The lens "hunted" on both my f100 and my f6. The company that sold it will accept my return - class act.