Mounting lens with T-mount on lens board

[godfatherofpolka]

(I'm new to this forum, so my apologies if this is the wrong place. And many thanks for any help in advance!)

I've got an old Beck Symmetrical lens (more or less like the ones that you usually see on Thornton-Pickard half and quarter plate cameras), but unfortunately, the mounting ring/flange is missing. Interestingly (?), the lens seems to perfectly fit into a T-mount, i.e., a screw mount with 42 mm diameter and 0.75 mm thread pitch.

I probably will be able to mount this lens using one of the T-mount to Nikon/Canon/Sony/YouNameIt adapters that are readily available (sawing/filing some parts off, if necessary, drilling some holes, etc.). However, I was wondering, if there is a better solution. T-mounts are not that unusual and I was wondering if there was any solution that was specifically made for mounting T-mount lenses on lens boards, i.e., a mounting ring/flange with the dimensions mentioned above? (Bonus: If anyone happens to know where such a thing might be available in the UK, that would be great).

 

[paul_c5x4]

T-mounts are not that unusual and I was wondering if there was any solution that was specifically made for mounting T-mount lenses on lens boards, i.e., a mounting ring/flange with the dimensions mentioned above? (Bonus: If anyone happens to know where such a thing might be available in the UK, that would be great).

Well...... A Copal/Compur #1 shutter has a 40mmx0.75mm thread in the front - If your lens doesn't have a shutter (which it probably doesn't), this would kill two birds with one stone.

As it so happens, I have a dead/broken #1 shutter - I'll have a look to see if is possible to remove the front threaded portion & if it could be mounted on a board. Added bonus is that it is in the UK already

P.S. Welcome to the forum. You'll find a wealth of knowledge, advice, and idle chat to be found here.

 

[Ian Grant]

My Half-plate T-P Beck Symmetrical is just over 8.5" FL and a similar lens off a Whole plate camera is around 11". my Wray 12" is marked 8"x5".

Anyway my point is I think you have a Quarter plate Beck Symmetrical the threads on my half plate lens are closer to 46mm (they would be Imperial tough).

Welcome to APUG BTW.

Ian

 

[godfatherofpolka]

@Paul: Thanks for the idea, I didn't think about using shutters, as I normally work with rather slow speeds, so a hat is enough If I see it right, however, the Copal/Computer #1 is only 40mm, which would not be enough as the lens is 42mm?

@Ian: Thanks for the information. I have virtually no idea about the history of the lens. Focal length is somewhere around 8", f8-45, only inscription is "Beck Symmetrical Lens" and it has a removable rear element. There's a good chance it came from a quarter plate camera, it seems to cover half plate, though. The diameter seems to be exactly 42mm (it perfectly fits a T-mount adapter I had lying around), which is somewhat odd, as one would expect a more imperial measurement, as you point out. Maybe there were export versions?

PS: Thanks for the warm welcome to both of you! I'm looking forward to the wealth of knowledge, advice, and idle chat and hope to be able to provide a good amount of it myself.

 

[Ian Grant]

It'll be Imperial but some threads will mate with the closest metric. I have a small box full of flanges around 30-40 now but can't lay my hands on it at the moment.

Ian

 

[paul_c5x4]

@If I see it right, however, the Copal/Computer #1 is only 40mm, which would not be enough as the lens is 42mm?

Sorry, my mistake (I posted way too early in the morning). You are right, a 42mm lens will not screw in to a 40mm hole, even with the aid of a large hammer.

If you can find a Compur #2 (very rare) or a larger #3, an adaptor can be made so that the lens will screw in - I did this with a dinky little 3" Beck some time ago.

 

[Whiteymorange]

Cheap, possible solution: Perhaps the mounting ring from the front of an old donor 35mm? I have a Canon body mount (FD) from a camera that died and I can use the T mount adapter on it. The body mount has screw holes in it that would allow mounting on a board. You might get the added fun of trying FD lenses on the LF camera.

 

[godfatherofpolka]

Thanks, yes, using a mounting ring from a donor body sounds like an interesting idea (with the additional fun you've mentioned), I will see what I can find (and update here once I have a working solution). Thanks for all the help!