5x7 holder compatability / Canham

[Don Dudenbostel]

A couple of months ago i purchased a used Canham 5x7 with both the 4x5 and 5x7 backs. First let me say it's a fantastic camera. Over the past 4 decades i've used my Sinar Norma and Deardorff 5x7's with no issues concerning compatability of holders. Now with the Canham I can no longer use the older Eastman and a couple of other brand holders that I used with the other cameras. Today I discovered the raised light rib on these holders is as much as 3/32" closer to the top of the holder in one brand and about 1/16" in the Eastman. I looked closely and the groove in the back where the rib seats is too narrow and the tolerences are so tight that some of my Lisco and Fidelity plastic holders won't seat either. In the Sinar back the groove is much wider and allows all the holders to seat properly. I was wondering if it's just my Canham back or if others have had this problem. To solve this I'm going to take it to my brother that is an acoustic musical instrument builder and have him remove about a 16th of an inch of wood which should solve the problem.

Thanks!