New Lens Issues

[collaborativeexpo]

I just purchased the Nikon AF Nikkor 50mm f/1.8 D.

For the next while I'll be working solely with a Nikon D3100 body, and I had a question about the Auto Focus.

The lens has the capability to auto focus (at least I assume it does from the AF in the product name), but I cannot seem to figure out how to get it to auto focus.
I have a sneaking suspicion that it will only auto focus with certain camera bodies, but I wanted to post here and find out if anyone had any insight.

Thanks to anyone who has any sort of theories or answers

 

[pthrift]

With the d3100 you need a lens that says af-s. If you purchased new its about a $220 lens. If you purchased the $115 version which only says af then it wont auto focus on your 3100

Sent from my Samsung Galaxy S4. probably at work.

 

[Pejacre]

I believe that lens will only auto focus on bodies with an integral focus motor, such as the d7000 or higher. For a D3100 body you need AF-S lenses which have their own internal focus motor.

 

[pthrift]

The difference is the higher end bodies from nikon have auto focus motors built into the body, where as your 3100 has to have the auto focus built into the lens instead

Sent from my Samsung Galaxy S4. probably at work.

 

[KmH]

The D3100 is a 'compact' Nikon.
To make it 'compact they left out the auto focus motor and screw drive the AF 50 mm f/1.8D needs to AF.

The motor/screw-drive is the only part of the AF system missing. The D3100 will turn on the viewfinder In Focus indicator when manual focus has been achieved.

But the D3100 has a manual focusing aid known as Rangefinder mode. See page 144 of your D3100 Reference Manual.
Rangefinder mode is not available when using Manual shooting mode, but the camera will still light the In Focus indicator in the viewfinder when manual focus has been achieved.
Also see page 167 - Compatible Lenses. it shows there is no auto focus with AF-G and AF-D Nikon lenses.
Also look at note #7 regarding the in focus indicator and some other Nikon AF lenses..

The higher level Nikons that have the auto focus motor/screw-drive system only use it for AF=G and AF-D lenses, not for AF-S lenses.