Quote Originally Posted by EdSawyer View Post
APO as referred to by the APO nikkor is not true APO either. You have to go to the Apo El Nikkor if you really want truly corrected apochromat performance. The Nikkor-T will be better corrected for "normal" photography, e.g. not graphic arts at close to 1:1 and with monochromatic light, which is what the Apo Nikkor is designed for. I would take the Nikkor-T over the apo-nikkor.
I agree, the "APO Nikkor" is more "APO" than the similar "Process Nikkor" and "Nikkor-Q", but I wouldn't say a T is less APO than APO-Nikkor.


Quote Originally Posted by tgtaylor View Post
I would guess that the apo-nikkor would be optically superior for reason that:

1. It's front element, which is coated, is larger resulting in a greater light capture per unit of time.
2. Tt focuses the light rays directly onto the film and does not bounce those rays around to make up for the shortened bellows.

Of course I could be wrong.

Thomas
Well, perhaps I wouldn't say that an APO Nikkor is better than a T for distant subjects. A Process/Reproduction lens is optimized for close projections, 1:1 or 1:5 (x1, x5 scale, better said), not for infinite. While a taking lens may work best from 1:10 or 1:20 magnifiction. So a test would be required to compare...

APO Nikkor is said to also work well for distant subjects, but it would be interesting to know the lp/mm depending on aperture for distant focus.


Another factor is the nice coating in the T if we plan to shot into the sun, anyway in that situation the critical thing is a front hud, because if not 80% of the circle of image (if 4x5) will be illuminating the bellows inside, with rays dancing there and ending in flare.

Finally the T is very fieldable if we add (to what said) that we can haul 2 additional rears to have 3 long focals. And three long focals in the backpack are not a joke


Both the T and the APO Nikkor are simple designs that trade having small coverage angle for other things. In the APO Nikkor absolute priority is focus field flatness and negligible distortion for repro environment. I guess the T priority is fielding 3 long focals, and this includes saving bellows draw, and smaller filters, while still having excellent Pro performance.