View Full Version : Lens Mount

r,l, Vigurs
25-Aug-2005, 19:02
I puchased a 210 Symmar S with a 4x5 at a vey good price. The lensis a perfect 12907678. It came in a Prontor shutter. Very limited. I have a 180 Symmar in a Synchro Compur. I found that the two main lens assemblies fit perfectly(210) into the Compur, but focus is very slightly off, as I assumed it would. Any ideas? Can I space the elements myself? Is there some one good, who at a reasonable price, could set this up for me? Appreciate any info. I'm in Santa Cruz, Ca. Thanks, Leagh.

Ernest Purdum
25-Aug-2005, 21:21
The first step would be to measure the overall thickness of the two assemblies, first the Prontor, then the Compur. If the Prontor turns out to be thicker, you only need a shim to correct the assembly in the Compur. If the Compur is the thicker, then correction will probably be difficult and expensive. Should this be the case, though, I woldn't think the problem would be too great to live with, since most view camera exposures are rather long. (I am assuming that you mean by "limited" that the Prontor lacks higher speeds.)

If your Compur is old. it may be that a modern shutter would do the job, since the Symmar-S isn't all that old. Your lens takes a "Number 1 shutter. Schneider listed the nominal overall thickness as 73mm.

If you can't find someone locally to measure the two, I would be happy to do it for you, just send me an email. It is, however, a very easy task for any machine shop. There are, I think, a number of them over the hill in the San Jose area. The most accurate way of making the measurement is by means of a surface plate and a height gage. With care, though, a dial caliper should give an adequate comparison.