Archived posting to the Leica Users Group, 1999/03/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>I researched this about a year ago and came up with this excellent page >listing mount to film plane registers. > >http://www.a1.nl/phomepag/markerink/mounts.htm > This page got a mention a while back. It states both M and R flange focal distances incorrectly. M should be 27.35 mm R should be 47.15 mm. And now here's a bit of interesting information. Hey, you at the back, stay awake. The ffd for Arriflex is 52.00 mm - that is the optical depth. Cameras are set so that the image is in focus 0.015 mm into the film, to allow for the thickness of the three layers. The flange to film surface distance is 51.895 mm. Give or take a yard or two. The optical path length from flange to surface of ground glass is 52.00 mm. Does anyone know if Leica allow for emulsion thickness in the same way? There now, wasn't that worth the effort? Regards, Malcolm Singapore