To put it nicely, the Quantarays are not very good lens. It's Ritz house lens that are produced to sell in their stores. The other two lens might not have internal motors for auto focusing(can't tell without the exact model name) and the camera is having problems getting a focus. Go to a photo store and ask to try out some of the current Nikon lens for your camera. They usually allow you to put in on your camera and test.
For the D80 you'll need an AF-S or AFI lens.
I have a Nikon D80 which I bought roughly 2 months ago. I already owned a NIKON kit lens from my N55 which I believe was in the range or 30-80 mm. I also already owned a Nikon 75 - 300mm lens (or something close to that). When I purchased the D80 it came with a Quantaray 75-200 mm lens. I have taken a lot of great photos so far with this camera, but I have found a problem that I cannot resolve.
With any of the lenses - even the new one. The autofocus takes forever to focus on objects. I did a test were I sat in a chair and focused on a lamp roughly 6' away. I would switch to manual and defocus the camera. Then switch back to AF and attempt to focus on the object. The quickest I could focus was at least 5 seconds with the newest lens. Is this normal? All the camera does is bounce the autofocus motor back and forth until it finally gets a lock. Should I return the camera? What do you think? Thanks!
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