Hi I am new member, I have NIKON D5100, yesterday after changing my lens I find one black dust spot in viewfinder but not in image.(Checked with zoom). So I guess it is in mirror or focus plane. I tried with blower to clean it, but it is still there. Please advise. the product is under warranty. Please advise.
#1. "RE: Dust in ViewFinder(D5100)" In response to Reply # 0
Welcome to Nikonians! Sorry to hear of your problem.
Dod you use a Rocket Blower? The dust is most likely on the bottom of the focusing screen just above the mirror.
Another possibility though unlikely is the dust is between the focusing screen and the penta-mirror. You would have to remove the focusing screen to get access. To do it yourself you will require a few tools and it is not difficult. Here are instructions for removing and replacing the focusing screen. If you don't feel comfortable send it to Nikon or a Nikon Authorized Repair Station.