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Forums > Back > Minolta F.W. Rokkor-QF 1:5.6 f=200mm lenses
#1
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:
[Image: 84B088D0963C48B99E66F59933D1BA5F.jpg]
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#2
So we are both on a weird Minolta vintage trip.

But you clearly won the coolness cup here ;-)
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
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#3
And you are clearly more sensible with the old and Minolta weirdness
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#4
Lend it to Markus to test. Smile
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#5
FWIW, "Rokkor" refers to Mount Rokko in Japan where the Minolta HQ used to be.

https://en.wikipedia.org/wiki/Mount_Rokk%C5%8D

Cool name and a bit strange that they abandoned this in the 80s.

The Minolta history of the 60s/70s is actually quite interesting. It's hard to believe today but during this time, they were actually leading the pack it seems. They had their own glass manufacturing and were the first with more advanced coating - as well as meter coupling. BTW, MC Rokkor means meter-coupled, not multi-coated (which they were as well).
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
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#6
(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:
[Image: 84B088D0963C48B99E66F59933D1BA5F.jpg]

  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 .......


https://www.ebay.fr/itm/304392306678?gclid=Cj0KCQjw37iTBhCWARIsACBt1Iy92L_VZ7usILPzMVQE2EwyoszdVgoAo7r5JCUFSr3PObJIj0bYYEcaAmY6EALw_wcB&_ul=FR&var=0&mkevt=1&mkcid=1&mkrid=709-53476-19255-0&campid=5338666530&toolid=10044&customid=Cj0KCQjw37iTBhCWARIsACBt1Iy92L_VZ7usILPzMVQE2EwyoszdVgoAo7r5JCUFSr3PObJIj0bYYEcaAmY6EALw_wcB

here's some details:

it will cover 8X10" ....... may cover 11x14" no iris ....... 

that's all folks!

an
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#7
Dave, I have found no real info yet. No idea in which machine kind/model they were used, no idea on the actual intended format and related to that, the distance to the image plane is also an unknown. They are a wide open only lens (so no adjustable aperture), and indeed are compact. "filter size" about 64mm, and the barrel length is 57mm. The used mounting plates have a 111mm diameter. Now you can have a sense of scale.

Maybe it was used in a copy machine like this:
https://www.konicaminolta.com/jp-ja/newsroom/2018/img/1019-01-01-02.png
(U-Bix480 from 1971)

A copier like this would at least be able to copy A4 (about 21 x 30cm), so 8" x 11.8"
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#8
I tried something: window about 3.5 meters from the wall, the window frame projection gets to be sharp with the back of the lens about 20cm from the wall. Of course, the lens would be designed for more close up subjects, and the distance to the image plane would be larger.
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#9
(05-02-2022, 12:16 PM)Brightcolours Wrote: I tried something: window about 3.5 meters from the wall, the window frame projection gets to be sharp with the back of the lens about 20cm from the wall. Of course, the lens would be designed for more close up subjects, and the distance to the image plane would be larger.

Hmmm ... some sort of projection or scanning lens maybe .... do you see yourself using it ....... if so what for ???
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#10
It should be good for close focus 200mm stuff, maybe closer than my 70-200mm f4? Perhaps the lens also may perform quite well with medium to infinity distance stuff (but just using the 70-200mm f4 will make more sense for that, of course).
My former large format project stalled due to that I was unable to compile the changed code needed to bypass the light/lamp need for the scanner I wanted to use. But if a new driver solution surfaces that I can use on my computer, I could use this lens as wide angle wide format lens, next to the 400mm f4 that would serve as a "normal" prime.
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