I am really confused on the backfocus requirements for the Explore Scientific 2" Field Flattener. I read on several websites that "Working distance = 1.77" / 45mm". However, I read on forums that it is 55mm.
From what I have also read the 55mm is for DSLRs and 45mm is for CCD/CMOS? I just want to confirm this.
Also, from where on the flattener is the measuring point for proper backfocus?
Many thanks for any helpful insights