thread adapters

Im still thinking and hunting, and have stumbled upon the pentacon 6 mount. And am seeing adapter mounts to use 35mm lenses on a medium format camera.

Just what the heck happens when you open up a 100-300 mm 35mm lens attached to a P6 mount medium format camera?

The flange to film gate distance is longer on a P6 mount so you can't focus at or near infinity.

There are/were lenses diseigned to cover 35mm & MF and I can think of one that was sold for 35mm up to 7x5 inches.. The Carl Zeiss Jena f2.8 180mm (Olympic) Sonnar was available with adapters for 35mm (various) and P6, as was the 300mm f4 Sonnar.

The older post WWII Schneider 360mm f5.5 Tele Xenar was available in a Compound shutter hutter for LF use 5x4 and 7x5, it was also sold in a barrel for M42, Exacta, Praktina etc but these were fixed barrels not adaptable to P6. The P6 barrel version cold be adapted to 35mm.

So instead of thinking a 35mm lens, go the other way around and a P6 lens for dual use on a 35mm camera.

Ian

Another thing is the coverage. You not necessarily can rely on the focal length. As lenses designed for 35mm cameras are designed for 43mm image circle they not necessarily cover a greater diameter.