Micro Nikkor 55/3.5 AI: is the DOF for Real?

[FilmOnly]

I bought a Micro Nikkor 55/3.5 AI. It arrived last week, and I started using it a couple of days ago. I notice that the highest number on the focusing ring is 15. Even at f/5.6, I can get somewhat close (hyperfocally) to the "15." Thus, it would appear that there is what I would consider enormous depth-of-field in this lens, particularly for a 55mm lens. Is this correct, or is there something I am missing? My Canon FD BL 55/1.2, as good as it is, does not get anywhere near this type of DOF.

 

[dynachrome]

55/3.5 Micro Nikkor DOF

I think you are confused about the markings. I am looking at a 55/3.5 'K' Micro Nikkor. This is the model just before the AI. It is the same optically and mechanically as the AI but has the pre-AI metering functions. If you turn the focusing ring so that the 15' mark is at TDC (top dead center) you will see there is a lot of depth of field between the outer set of DOF markings. On the 'K' lems these outer markings are blue. Why does the depth of field look so great at the outer markings? Because it assumes you are shooting at f/32. Your Canon 55/1.2 FD lens has the same depth of field as the 55/3.5 Micro Nikkor from f/3.5 down (to smaller apertures). The difference is that an f/1.2 standard lens will typically not stop down to f/32. Even with the Micro Nikkor, shooting at f/32 would cause diffraction and lower overall sharpness. You would only use f/32 if you needed extra depth of field or because a wider f/stop would let in too much light.

 

[FilmOnly]

I have both lenses in my hands. I see exactly what you are describing. The Nikkor is not as intuitively marked as the Canon. When I look at my FD BL 55/1.2, the DOF range is more informative. There is a "30" marking between "15" and the infinity sign. Also, there would seem to be better spacing on the Canon lens. In any case, I am sure the Nikkor will produce nice photos. I have heard that it is extremely sharp.

PS: With regard to diffraction, I could not agree more. I rarely go beyond F/11, as I have noticed diffraction at f/16 (let alone f/32). I cannot remember the couple of lenses that showed some diffraction at f/16 (it was a few years ago), but they were decent quality primes. The prints looked fake, flat, and darkish. The colors were not quite right, either.