Advice: Leica BEOON for Scanning

[Doug A]

Good to know! I wonder if some enlarger lenses, like normal taking lenses, vary slightly from the stated focal length.

I'm sure there are some very small variations in focal length. But the big issue with trying to copy someone else's BEOON setup with a different enlarging lens is that there is no standard for the distance between the focal node of the lens and the mounting flange. Enlarging lenses have no focusing capability built in. They are totally dependent on the bellows or helical focusing of the enlarger.

 

[Doug A]

Thank you all for your answers and ideas... given my preference to use an enlarger lens and APSC, I think I'll just sell the BEOON to fund an old copy stand and bellows unit. Given prices of the BEOON these days I'll probably have $$ left over.

You would certainly have a more flexible arrangement. My BEOON setup is super fast and super easy to use for 35mm. For 6x6 negatives I have a choice between using a 40mm Nikkor enlarging lens with a different extension tube and a negative carrier from an old Omega enlarger under the BEOON base or making six exposures of each negative with my 35mm setup and stitching the images together with Panorama Stitcher. Neither is fast or easy.

 

[rfaspen]

Using a BEOON requires an initial effort to find the combo that works for you and your gear (I use an EL Nikkor 50/2.8, FF Leica). But, once you arrive at the setup, you have a very fast, compact (easily stored), setup that is rigidly pre-aligned and set. So fast and easy to use. The physical part of scanning 35 negs goes lightning fast every time you sit down to a scanning session. Now, MF is definitely more of a pain. If you scan a lot of MF, the BEOON might not give any substantial advantage. So it comes down to that for me. I don't scan much MF.

 

[Ricoh]

I'm sure there are some very small variations in focal length. But the big issue with trying to copy someone else's BEOON setup with a different enlarging lens is that there is no standard for the distance between the focal node of the lens and the mounting flange. Enlarging lenses have no focusing capability built in. They are totally dependent on the bellows or helical focusing of the enlarger.

After many attempts of getting a rigid non-helicoid set up on the Beoon to work using an enlarger lens (I’ve tried both the Nikkor 50/2.8 and Schneider Componon S green stripe 50/2.8) I’ve given up and returned to using my Summilux 50/1.4 set to f8 or 11. Works perfectly with the M240.
Reading this thread has awakened my recollections of messing with enlarger lenses. I’ve never really understood where the focal node is on a lens, or how to measure it if possible.

 

[Doug A]

Reading this thread has awakened my recollections of messing with enlarger lenses. I’ve never really understood where the focal node is on a lens, or how to measure it if possible.

The optical node of a lens is the point, usually somewhere inside the lens*, from which the distance to the film plane (the focal length) is measured. With a simple magnifying glass (technically a biconvex symmetrical lens) the optical node is at the physical center of the lens. With a lens made up of multiple elements of different curvatures and refractive indices there is no easy way to measure its location. With a camera lens the approximate location can be determined by mounting the lens on a compatible camera, focusing the lens to infinity, and using a ruler or caliper to measure the stated focal length of the lens out from the film plane mark found on many cameras. Obviously this can not be done with an enlarging lens.

*With a true telephoto lens the optical node is physically out in front of the lens, i.e., the physical lens is shorter than the focal length.

 

[Ricoh]

The optical node of a lens is the point, usually somewhere inside the lens*, from which the distance to the film plane (the focal length) is measured. With a simple magnifying glass (technically a biconvex symmetrical lens) the optical node is at the physical center of the lens. With a lens made up of multiple elements of different curvatures and refractive indices there is no easy way to measure its location. With a camera lens the approximate location can be determined by mounting the lens on a compatible camera, focusing the lens to infinity, and using a ruler or caliper to measure the stated focal length of the lens out from the film plane mark found on many cameras. Obviously this can not be done with an enlarging lens.

*With a true telephoto lens the optical node is physically out in front of the lens, i.e., the physical lens is shorter than the focal length.

Thanks Doug A.
Based on previous threads I’ve read on using a Beoon with an enlarger lens, and my own experience compared to another using the same make and model of enlarger lens, it suggests to me that such lenses are not necessarily identical. In fact, as you touched on earlier, there’s no need for absolutes given enlargers have an adjustable column height, eg rack and pinion.

 

[Doug A]

Thanks Doug A.
Based on previous threads I’ve read on using a Beoon with an enlarger lens, and my own experience compared to another using the same make and model of enlarger lens, it suggests to me that such lenses are not necessarily identical. In fact, as you touched on earlier, there’s no need for absolutes given enlargers have an adjustable column height, eg rack and pinion.

It would indeed be interesting to know how much variation there actually is.

 

[Ricoh]

This may be of interest to some, digitising B&W film using the monochrome M246.
https://www.streetsilhouettes.com/home/2019/10/3/digitizing-black-and-white-film-with-the-leica-m246

 

[Arjan4130]

Anybody had succes using a 50mm enlarger lens on a Beoon and a asp-c sensor for 120 film?
35mm was sorted quickly but I seem to run out of column length for every extension tube combo that covers a 120 negative.

I’ve read some posts of people who use a 40mm enlarger lens for 120 film on the Beoon+aps-c. So I am wondering if maybe a 50mm on aps-c just won’t work for 120 on the Beoon. Or I just can’t get the right extension length..

For some background: I have had the Beoon for quite some time. Tried it with my Leica M9 but had trouble getting accurate focus through the Beoon loupe. So I decided to switch to a Sony with a asp-c sensor. I got the Beoon tubes and a focussing helicoid extension (10-15mm). I am planning to use the valoi.co holders. But first need to get the negative within reach.