Upload & Sell: On
In Feb this year, I bought a NIB d7k and didn't get much shutter time with it (just some test shots at close distance inside the house) until well beyond the time where the return period had expired.
Seems like my d7k has a backfocus issue, but only at longer distances, like 75' or so. For example, at/near infinity focus at 300mm, the subject is OOF and actual focus seems to be behind the subject. At closer distances and shorter focal lengths, the issue goes away. Unfortunately, I don't have any test shots that can demonstrate this clearly. Sorry that I haven't any good demo images, but when I found the problem, I put the d7k on the shelf and went back to using the d300.
This seems pretty weird to me. I don't recall ever reading about BF only at certain distances. So, I'd like to know if others have encountered this issue and if Nikon service can fix it without goofing up the rest of the AF.
I'm not sure how to go about making samples for Nikon service that can easily demonstrate the issue at long distances. I'm thinking about putting a bunch of AF test targets on a large piece of cardboard and then lay that down on the ground behind a vertical subject target. Any suggestions on how to better accomplish this task would be welcome. I'll be testing with several long lenses. I want to make sure that I can easily demonstrate where the problem lies and make sure that it's not just this particular lens that the d7k doesn't like.