Nikon ai and ais lenses.

[Stephen Furley]

On Nikon bodies such as rge FA, F-301 and F-501 which have the extra pin in the lens mount to detect when an ais lens is mounted what advantage does an ais lens give over an ai one?

 

[Nitroplait]

Aperture automation (S) and Program automation. Ai only allows shutter automation (A).

 

[benveniste]

On Nikon bodies such as rge FA, F-301 and F-501 which have the extra pin in the lens mount to detect when an ais lens is mounted what advantage does an ais lens give over an ai one?

On those bodies, an AI-s lens gives the following advantages:

• In S mode, you actually get the shutter speed you set. With non-AI-s lenses, the camera corrects for the non-linear aperture action by taking a mirror-up exposure reading and adjusting the shutter speed accordingly.
• In P mode, the camera makes a similar adjustment. This is also the case with the Nikon FG.
• On the FA, the camera detects that a long AI-s lens is mounted and favors faster shutter speeds for program mode. On the F-501/N2020, the camera does the same thing in P-Dual mode. I'm not sure about the F-301/N2000, but on both the F-301 and F-501 you can choose P-Hi mode instead.
• The F-301 and F-501 only allow "Programmed TTL Auto" with AI-s and series lenses.

These are not massive advantages. I never bothered to "upgrade" my 50mm f/1.8 AI long-nose, and still have both it and my Nikon FA.