Summilux 75mm 1.4 with Leica M9

[Rob-F]

This is likewise what I was told by a tech at Leica's US facility when I inquired. What I was told was that because of the nature of film, the tolerances to the calibration didn't need to be as precise as for digital. Lenses now calibrated required additional work to insure less 'leeway' when adjusting the moving parts of the focus system to insure that precision time and again during regular use. More time consumed = greater cost

Ok now we are talking about tolerance? Until now the comments have been that lenses for digital have to be "calibrated" differently than for film, as if there were a difference in the distance from the lens's principal plane or rear nodal point, to the image (film or sensor) plane. Whereas to say that the tolerances are tighter or more critical, is a different thing. That just says that greater care must be taken to ensure the lens is very accurately adjusted to the correct setting; not that the correct setting differs between film and digital.

So another way to say it is that with film, the focus had to be within a millismidge, but with digital, it needs to be within a microsmidge, maybe even a nanosmidge. Not that the distance from lens to image plane is different.

 

[Freakscene]

Ok now we are talking about tolerance? Until now the comments have been that lenses for digital have to be "calibrated" differently than for film, as if there were a difference in the distance from the lens's principal plane or rear nodal point, to the image (film or sensor) plane. Whereas to say that the tolerances are tighter or more critical, is a different thing. That just says that greater care must be taken to ensure the lens is very accurately adjusted to the correct setting; not that the correct setting differs between film and digital.

So another way to say it is that with film, the focus had to be within a millismidge, but with digital, it needs to be within a microsmidge, maybe even a nanosmidge. Not that the distance from lens to image plane is different.

Correct. Leica built new equipment to achieve it too, but the ideal focus point is the same for film or digital, and properly adjusted lenses will work on your digital and film Ms, again assuming the rangefinder in the camera is properly calibrated. To aid this, the typ 240 and later rangefinders were reengineered, at least partly so they hold calibration better.

Marty