[Konvas] 16mm -> 35mm lens (a silly question)

[Adam Frey]

I'm going to ask this, even though it may seem just plain silly...

Is it possible to take a lens made for a 16mm camera and up-convert it 
to 35mm?

Let's use a plain old C-Mount lens as our example, since it has been
such an industry standard for so many years. A C-mount lens has a one 
inch diameter and its Flange Focal Distances (FFD) is 17.526mm deep. The 
frame size that the 16mm lens usually covers is 7.5mm x 10.4mm (regular 
16 - no need to get into Super16 here).

The size of a 35mm frame is 16mm x 22mm. Konvas OCT-19 has an FFD of
61mm and a PL mount has an FFD of 52mm. Both have wider diameters than
the C-mount and can allow for someone to build an adapter for a smaller
lens to be seated inside (like a c-mount lens).

Since the C-mount would normally need to be extremely close to the film 
plane, my thoughts would be to install an achromat on the backside of 
the C-mount lens that will project the image to either the 61mm or 52mm 
film planes. In the process, the projection can also be expanded to 
cover the 35mm Cine frame. BTW: A decent achromat shouldn't affect the 
quality of the image, correct?

This will, theoretically, be able to project the image to the proper 
depth of a 35mm negative, although inverted, I believe (if inverted, a 
2nd achromatic lens would revert the lens to right side up, although 
that will, in theory, eat up more light).

I'm asking this for the obvious reasons, but the biggest is that you can 
easily find extremely fast 16mm cine lenses that are super sharp. The 
other thing is that instead of blowing $15,000 on lenses for a DOF 
adapter type of rig, you can pick up a set of decent 16mm Cine lenses, 
slap the converter on the back of them and have an equally good lens set 
for a few grand instead and 16mm lenses are often sharper than most 
standard 135 (still 35mm) lenses.

Just some thoughts... Just some thoughts...

Cheers,

Adam Frey
Director/Cinematographer
Crimson Chain Productions
http://crimsonchain.com

Crimson Chain Productions
PO Box 35
Libertytown, MD 21762