|Posted: Sat Apr 13, 2019 6:59 pm Post subject:
You can also manually confirm the back-focus/registration distance (project an image onto a wall)
Place a lamp 2-3m away from a wall, set the lens to 2-3m, get the lamp in focus, and measure to the wall from an easily measurable point on the lens, then figure out from that point where the mount flange is and subtract the difference. you should be close to 42mm.
Note: The FL/FD mount flange is buried in the lens mount.
Hi Lightshow, I measured the Flange Focus distance as you suggested, is 42mm as expected.
I removed the front optics, this group has never been disassembled, i saw a unbroken seal (similar to that seen on the rear optics) between the retaining ring and the optics.
So the lens seem ok.
I think there is no room to move back the optics without drastically modify it.
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