A friend of mine sent me these pics of a Nikon 35mm F2.8 lens that had been modified in the following way -

the normal aperture control ring and the aperture control linkage had been removed, and a very large knurled aperture control ring substituted.

anyone have a WAG (Wild-Ass Guess) as to what they could be?

Fat or arthritic fingers?

Perhaps- but then why the removal of the auto-aperture function, and why put the aperture numbers on so they would be upside down when looking at them from the viewing end of the camera? It looks like they might have modded this to use as an enlarging or macro lens on a bellows...

My guess is... to work as an enlarging lens, so as not to bump the focus when stopping down?

It could also be a cine conversion; the Nikon bayonet mount is very common in aftermarket modifications of motion picture cameras like the Fries Mitchell Conversions.

However, in most conversions I have seen where the lens is modified, the focus barrel is the same size (or larger if used with a mattebox and follow focus) as the aperture ring, so I would tend to vote "copy lens".

My only question is would a normal 35mm lens be corrected enough for high magnification close-up, copy work or enlarging? I know that special close-up lenses have been made like the Canon Macrophoto lens and lens by other makers, but these are specially designed and corrected for copy, close-up and enlarging usage.

Rich

Could be for use on a machine vision camera. This could often be an unusual environment, so easier set-up then leaving the lens might be common. The other possibility would be for usage in a housing, such as underwater, machine vision, or explosive environment.

Just an aside on this particular lens, the 35mm f2.8 normal lens is nothing special as far as construction. The shift version is completely different, and the faster normal versions are considered by some to be much better choices.

Ciao!

Gordon

Could be for use on a machine vision camera. This could often be an unusual environment, so easier set-up then leaving the lens might be common. The other possibility would be for usage in a housing, such as underwater, machine vision, or explosive environment.

Just an aside on this particular lens, the 35mm f2.8 normal lens is nothing special as far as construction. The shift version is completely different, and the faster normal versions are considered by some to be much better choices.

Ciao!

Gordon

I'd second this, we use Nikon lenses on 3 separate instruments, 17 in all. Although none are modified apart from a locking collar fitted to prevent accidental adjustment.

Cheers