Indeed Chuck's recommendation will get you back to this years earlier Mafac conversation. But much of what transpired happened off list by a few interested people. The photo album that was posted and may still be "linked" there is no longer up. And I believe the chart I refer to was not discussed or posted to list. So assuming Ive got that right Im happy to help anyone connect with this stuff from my personal files.
Tom Rawson
Oakland, CA