Anyone want a new-production extended lensboard like Beseler #8088?

[Steve Goldstein]

The Beseler 8088 lensboard was designed specifically for the 150mm Apo-Componon-HM enlarging lens, which was difficult to place and remove on a Beseler 4x5 enlarger when mounted on a flat lensboard. It gave about 1" of extension, which sufficed for the rear element to clear the housing. Beseler lists it as discontinued, although B+H show it as a special-order item here: https://www.bhphotovideo.com/c/product/4527-REG/Beseler_8088_Lensboard_with_Extension_for.html

I will be making the functional equivalent of this board with a 50mm mounting hole (the 8088 had a 55mm hole, I believe) for my recently-acquired 180mm Componon S. Unlike the original version, which is assembled from pieces, it will be machined from a single piece of aluminum in a friend's 100%-CNC machine shop. While we were discussing this project he asked me if there's wider interest in these. Once the machine is programmed, the effort involved in making additional copies is low, primarily material cost and machine time. He estimated the unit cost at about US$100 exclusive of shipping.

So I put it to the community at large - does anyone else want one of these with either 50mm or 55mm mounting hole? Please respond here rather than by private message (= conversation in Photrio-speak). We will definitely be making one for me, the question is whether to order additional materials to produce more. The deadline for expressing your interest is December 31, 2019. I'll order materials sufficient to produce the number requested early in the new year. This is a one-time opportunity - we have no plans to do this a second time.

I've posted this on both the Large Format Photography Forum and on Photrio, please only respond in one place so I don't double-count.

 

[ic-racer]

You could have one of these made too.

Or maybe the 50mm screw adapter for Omega (that fits on a flat plate) could be fitted to a flat Beseler plate?

 

[Steve Goldstein]

I'm not sure the ring in the first photo would do the job. The Omega adapter would be easy enough to use, assuming I can find one, but I don't know how much extension it offers. I'm aiming for 1-1/8", which is an available thickness for 6" x 6" aluminum plate from McMaster-Carr.

 

[EdSawyer]

Steve, an interesting project. Isn't the issue that the design of some of the Beseler 45 enlargers has a sort of plate with a curved opening above the lens stage, and the rear element of this lens (and others) hits that? As I recall I ran into something like that on my 45VXL. I think the plate with curved opening is to allow mounting/adapting the beseler lens turret? And another option rather than an extension board is to machine out this plate that restricts the lens rear element. It's been a while but I seem to recall doing that on my 45VXL to allow larger lenses with big rear elements to clear the area above the lens stage.

 

[Steve Goldstein]

My Beseler 45 has a squarish opening protruding inwards a bit above the lens stage; I think the (tapered) bellows is mounted to this. The 150mm Apo-Componon-HM has a longish rear cell, and I suspect the 8088 board was done because of complaints of bumping the rear cell into this "lip".

A side effect was that it was an extended lensboard, which is my real reason for doing this. It'll allow me to use a 180mm with only marginally more bellows extension than with a 150 for a given image size. Besides that, it's a fun little project. My friend was a photographer long before he was a machinist (that's actually a hobby, his real job is designing radio antennas) and he enjoys helping me with my nutty projects.

 

[ic-racer]

I'll be interested in seeing the final product. Will this be CNC machined from metal or 3D printed?

 

[ic-racer]

I use that Omega adapter for my 150mm Componon-S. The adapter provides clearance of the rear elements on the 3-way turret so it can spin without decapitating the rear lens elements.

 

[Steve Goldstein]

I'll be interested in seeing the final product. Will this be CNC machined from metal or 3D printed?

From my initial post: “...it will be machined from a single piece of aluminum in a friend's 100% CNC machine shop.”

i considered 3D printing (he can do that too) but was concerned about the strength of the material versus the force needed to install and remove the board. Metal will be stronger. Plus I get to watch the flood-cooled workstation, more front than a front-loading washing machine.

 

[ic-racer]

Yes, just was interested in your comments on 3D printing. I'm still skeptical of it compared to metal.

 

[Michael McGee]

Steve, I would be interested.

 

[Steve Goldstein]

Sent you a PM, i.e. started a "Conversation" with you.