Doug, I was also concerned about the discrepancy in the f/2.8-vs-f/4 when using the 14198 tube on the 100, but the 3rd cam (lug) acts to "nul" the meter properly. The camera is fooled into thinking that it has a "dark" f/2.8 lens on it and meters accordingly, even the R5~R8 TTL flash operated perfectly. Art ------ Unsubscribe or change to/from Digest Mode at: http://www3.telus.net/~telyt/lrflex.htm Archives are at: www.freelists.org/archives/leicareflex/