85 1.4 Choices

[Akira]

Ai has the "20m" mark on its focusing ring, whereas Ais doesn't because of the latter's shorter focus throw.

[Roland Vink]

I thought the best way to tell apart AI from AIS was the lens mount ?

AI and AI-S lenses are closely related: many have the same optics with more or less the same coatings, and the general appearance is also very similar. AI-S have one functional difference: the position of aperture stop-down lever has a linear relationship with the aperture opening (f-stop). This allows the camera to move the stop-down lever to set the aperture in P or S modes. Doing the same with an AI lens will give unpredictable exposures. AI-S is standard for all CPU lenses (except the new E lenses) but no current camera distinguishes non-CPU AI from AI-S, all are assumed to be AI which is why S and P modes are not possible.

AI-S lenses can be distinguished by:

• A small scoop in the lens mount, signals to certain cameras that an AI-S lens is used.
• Minimum aperture on the ADR scale is orange (ADR = Aperture Direct Readout, the small secondary scale near the lower edge of the aperture ring, visible through small window in viewfinder of AI cameras such as FM, FE, F3). Several AI lenses have minimum aperture on main scale in orange (or orange-brown) but ADR scale is white.
• Changes in styling - many AI primes have DOF scale on the barrel between the chrome and focus ring, on AIS lenses the DOF scale is generally on the chrome ring. The focus throw of AI-S lenses is usually shorter, and there my be other small differences.

Series-E lenses are AI-S, in fact they came to market two years before the official AI-S series.

[chambeshi]

One factor in lens selection that never entered my mind was emphasized by the late Galen Rowell. It's why I've now shifted the 85 f1.4 high up my Wants-List. And the well revered 80-200mm f/4.5n AI Nikkor is another :-)

This is for aerial photography. Rowell found the vibrations / turbulence in a light plane or chopper can knock an AF lens off focus even if it's set manually. He preferred manual focus AIS Nikkors for aerial photography, especially in bumpy light aircraft. Hence the 85 f1.4 was among his favourites:

"Because AF lenses set manually vibrate out of focus while shooting from a moving plane, I choose older manual lenses that stay locked on infinity. My Nikon 35mm f1.4 and 85mm f1.4 give me the highest possible shutter speeds to use with slow, sharp slide films. I try to shoot at over 1/1000 and consider 1/250 my slowest safe speed with my 35mm lens (1/500 for my 85mm)...." Aerial Wisdom, Outdoor Photographer, May 1996 http://www.mountainlight.com/articles.html

his equipment list here:
http://www.mountainlight.com/rowell/gr_camera_bag.html

video clip http://www.openroad.tv/video.php?vid=48

In my own experience in conservation surveys, I only had a manual lens on film camera. And in a Bell 'chopper and a SuperCub (very turbulence over granite landscapes on a hot day) I used a 55 f2.8 micro-Nikkor on a FM2 or F90x. And by chance or other, I got great results, and obviously with fast shutter speeds

[richardHaw]

simple is best <- my motto

[Hugh_3170]

Yes, the late Galen Rowell was very canny indeed in his lens and camera choices.  Where he was running or backpacking into locations he was not averse to carefully selected consumer grade lenses and cameras where weight was an issue.  His gear was not always top shelf in these situations.