I have a new D5100 and an old AF Micro Nikkor 60mm lens. It appears that it will not Auto Focus mounted on the D5100. I've got it in A mode (rather than M) but nothing. Should I conclude there is something wrong with the lens or is there some chance that the Auto Focus feature does not work with this lens on the D5100? Sure would appreciate some help as I use this lens often - used it with no problems on my D50 that I just gave to my daughter. Thanks - Joe
#1. "RE: Nikon Auto Focus" In response to Reply # 0 Thu 16-Feb-12 09:04 PM by jpFoto
Older Nikkor auto focus lenses don't auto-focus on the D5100 or the D3100 because those bodies do not have auto-focus motors. You need to use AF-S lenses on those two cameras because the lenses themselves have motors. However, you can still use the lens, but only in manual focus mode.
Take a look at the list pinned to the top of this forum for a list of lenses that will auto focus on the D5000 and D3000 (same type of bodies as the D5100 and D3100.
#2. "RE: Nikon Auto Focus" In response to Reply # 0
Welcome to Nikonians! Your D50 has an AF motor built into the camera body that drives the screwdriver AF mechanism of the AF, AF-D, and the older AF-G type lenses. To reduce the price of entry level bodies, Nikon decided to omit AF motors in the entry level bodies starting with the D40 about 5 years ago. At the same time, they introduced entry level AF-S type lenses like the 18-55mm f/3.5-5.6G AF-S DX. The bodies that don't have AF motors are the: D40, D40X, D60, D3000, D5000, D3100, and your D5100. As JP wrote above, the D5100 will provide metering when the older AF type lenses are mounted on the camera, but no AF. You will have to focus Manually. The D90, D7000, D_00 series, and D_ series bodies continue to have AF motors built into the camera body and are fully compatible with the screwdriver type AF lenses. Good Luck and Enjoy your Nikons!