Lens and lensboard help

[FM2N]

Hello All,
I have a very nice 210mm lens that I would love to mount on the Seneca Improved View that I just received but the lens board is 1/4 in. thick and there is not enough thread on the rear of the lens to get a threaded rind to grab and hold. Can I mount it on the front of the lensboard? I think I will need a flange of some sort but I do not know where to get these or the exact name they are called. Could I mount a thin step-up ring to the front of the lens board and attach the lens to this? How far out the back of the lensboard does the rear element have to be? It does not have to be pretty so any suggestions would be great.
Thanks
Arthur

 

[Ole]

A mounting flange can be put on the front of the lens board and the lens screwed to that.

Or you can make a recess in the back of the board - a wider hole which doesn't go all the way through - to allow the normal retaining ring to be used.

There's no need for the rear element to extend behind the lens board, as long as the edge of the hole doesn't intrude on the field of view.

 

[FM2N]

Thanks Ole,
Would you happen to know any places where I could get the correct flange for my lens?
thanks again
Arthur

 

[Nick Zentena]

Did the lens come without one then?

Mpex?

http://www.skgrimes.com/

If you already have a ring mounting like Ole mentioned in a recess is fairly easy with a wooden lensboard. Just drill two holes. One bigger then the ring a part way into the board. One the right size for the lens all the way. Fairly painless with a drill press and a forstner bit.

 

[Ole]

Thanks Ole,
Would you happen to know any places where I could get the correct flange for my lens?

It would be a lot easier if I knew what lens it is, and whether it's in a shutter!

for all I know, I might have one in my big box of odds and ends and rings and stuff...

 

[FM2N]

HI,
It comes in a Ilex shutter. The lens is a Bausch & Lomb Tessar Ser. 1c. The rear thread seems to be a 49mm but could be 48.
Arthur

 

[FM2N]

Thank you all for your help. I took Ole's advice and built my own lensboard and it worked out perfectly.
Thanks again
Arthur