(04-30-2022, 07:46 AM)Brightcolours Wrote: In a weird blackout I bought 2 of these lenses.
And because people die and interests shift, more and more info disappears from the searchable internet about old/industrial/obscure optics. So, there is little to no information to be found on the how and why of these lenses.
The little I have pieced together is: Copier/projection (for duplication)/reproduction lenses. The QF-part means 6 elements in 4 groups (Q for 4 in Latin(?), F probably the 6th letter of the alphabet) in old Minolta-speak. The F.W. describes the type of lens. I gather that it probably stands for Flat (so a corrected lens for a flat projection) and Wide (200mm giving a wide AOV for the intended use-format). Because of the lack of info, the exact intended AOV/FOV remains unknown.
There also are F. Rokkor-QF 1:6.5 197mm and F. Rokkor-QF 1:6.5 195mm lenses, which miss the W in the name. Safe to say that at the focal length probably is exactly 200mm...
They weigh a bit over half a kilo each with their mounting plates. The mounting plates have little Allen key screws to make sure the projected image is not tilted.
Now, what to do with them? And why 2? Dave lives too far away to just give him one. Should I figure out a way to use one for larger format photography, for its intended FOV? Or just "adapt" it to 135 format, and see how it renders (probably pretty smoothly) as 200mm FF lens with closer up nature stuff?
So many questions...
And the lenses in question:
Hi BC ........ have you established what the registration distance is ? and what is the maximum coverage (format) the the lens will cover ?? It looks to be quite compact ........ no aperture blades then?
here's one I found on ebay btw .......
here's some details:
it will cover 8X10" ....... may cover 11x14" no iris .......
that's all folks!