As a topic, what the diff. between AI and AIS? Can an old lens be AIS lens? I just saw good clean AIS lens cost $110 (for 28mm), why is it so cheap compare to the same exc++ 28mm AIS but cost about $250. Can it be an old lens but retrofit?And, if it is original AIS how old would it be? (you can estimate, for example, no longer than 20yrs because it first made in 19...) THANK YOU FOR ALL THE HELP!!

-- ik (ik_np@yahoo.com), February 24, 2002

Answers

AIS just adds a means for the lens to be able to communicate its focal length to the camera. It first made its appearance for use with the Nikon FA. It may also serve a purpose on other Nikon manual focus cameras. You don't need AIS for many Nikon models, like the FE, FE2, FM, etc.

-- Bob Fleischman (RFXMAIL@prodigy.net), February 24, 2002.

AiS added more than just the little focal length notch.
The aperture mechanism was modified on AiS lenses so that the stop down lever could be used to accurately regulate the aperture. A given movement of the stop down lever will give the same aperture on all AiS lenses. This isn't true for Ai series and older lenses.
An Ai, or pre-Ai lens can't be modified to make it AiS, but this isn't a big deal unless you own a Nikon FA. The FA was the only camera to make full use of AiS lenses.
If you notice, all AiS lenses have the smallest aperture marked in orange, to signify the shutter priority or program mode position. Check this orange aperture marking, and the 'scoop' on the back of the mount to make sure that a lens really is AiS. I've seen lenses being sold as AiS that were only Ai.

The E series lenses were all AiS compatible, I believe.

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 25, 2002.

If this is to complex and confusing you can alway switch to a Canon EOS system - all EOS lenses work exactely the same on all EOS bodies.

;-)

-- Can Onshooter (can@on.com), February 25, 2002.

I doubt if it's too complex for the intelligence of any Nikon user.
In fact it's very simple: All current AF and MF Nikkor lenses will fit all Nikon SLR bodies, right back to the original F model, and all Nikon SLR lenses fit on any Nikon SLR body (although some pre-Ai lenses might need a slight mod to fit cameras introduced after the FE).
How many mounts has Canon got through now? Is it 4 or only 3?
Talk about pots and kettles!

-- Pete Andrews (p.l.andrews@bham.ac.uk), February 25, 2002.

I see - it is very simple.

All Nikon lenses fit on all Nikon bodies.

All EOS lenses work on all EOS bodies.

-- Can Onshooter (can@on.com), February 25, 2002.

Well, thank you for all your help. I do learned a lot from you guys. Especially the way to check for "scoop" on AiS, it's very useful to me.

-- ik (ik_np@yahoo.com), February 25, 2002.