What is this lens?

I've received this lens from a friend today. He said something like "enlarger lens".

But this seems not to be correct. f/9 doesn't seem to be that fast, and which enlarger lens needs to be stopped down to f/260??

What is the use of such a lens?

regards,
chris

Its a process lens that can be used for general photography. From A Lens Collectors Vade Mecum:

What makes it special is that is of absolute symmetrical design. In contrast to enlarger lenses.

The Vade has some serial number dates: 4000000 - 1957; 5000000 - 1961.

Ok. Thanks. But maybe I need to rephrase my question:

I understand "macro work" and see the general usefulness of being able to stop the lens down to such insanely small apertures. Is this one reason for these small apertures? And doesn't diffraction work against picture sharpness then?

But what exactly is a "process lens" or "process work" ?

regards,
chris

Process Work means Repro Photographie in a print shop

AgX said:

Process Work means Repro Photographie in a print shop

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And for that, one needs excellent flat field performance at close focus distances.

swchris said:

Ok. Thanks. But maybe I need to rephrase my question:

I understand "macro work" and see the general usefulness of being able to stop the lens down to such insanely small apertures. Is this one reason for these small apertures? And doesn't diffraction work against picture sharpness then?

But what exactly is a "process lens" or "process work" ?

regards,
chris

Click to expand...

Your lens is at the short end of the scale. Most horizontal process cameras were immense. Small ones took 16x20 film, bigger 3x4 foot film and larger.
https://en.wikipedia.org/wiki/Process_camera

MattKing said:

And for that, one needs excellent flat field performance at close focus distances.

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Yes, but process lenses typically are optimized for scale 1/1, enlarger lenses typically are not optimized for 1/1 and this lens is advised for 1/1-infinite.

swchris said:

Ok. Thanks. But maybe I need to rephrase my question:

I understand "macro work" and see the general usefulness of being able to stop the lens down to such insanely small apertures. Is this one reason for these small apertures? And doesn't diffraction work against picture sharpness then?

But what exactly is a "process lens" or "process work" ?

regards,
chris

Click to expand...

hi chris
might as well use it and see how you like it
a lot of people who do LF work use GClaron enlarger lenses. they fit in one of the copal shutters directly ( I think copal 1? )
and I think I remember reading over the years people love them so much they have created "casket sets". ( a barrel with a bunch of interchangeable
GClaron elements to give a variety of different focal lengths ) .. if you ever have to do copy work ( rephotographing things like objects, maps or papers or prints or negatives )
your lens will be great too... I use a tominon 127mm lens which was originally on some sort of polaroid copy/process camera all the time. it was sold as the taking lens
on the speed graphic I bought back in the day and it works great..
have fun with your new lens !
John

Thanks all for the education.