Archived posting to the Leica Users Group, 2006/12/29
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> > Coupling means that the lens tells the camera what F stop it is set to. > This allows the camera to measure the exposure and set the shutter speed. > > > >> > This may be na??ve, but how can it not couple at 1.2? The diaphragm is >> > independent of the camera. >> > > ------------------------------ I think that the camera -M8- does not receive information from the lens unless the lens is coded by Leica, and nevertheless the meter calculates the right exposition through the "real" light coming into the camera. The coded information feeds the EXIF and the software in order the M8 can correct some defective issues of some lens as vignetting in wides. To say this I am based in the way my Canons work. When, using adapters, I fit a Leica -or Nikon- lens in my cameras -5D and 1Ds MKII- the internal software does not see the diaphragm and in the finder displays *00* but, very important but, the exposition is always correct working in A(perture). Not in Nikon DSLR where meter does not work with not CPU lenses excepting D200 and D1/2. On the other hand sensors in DSLRs do not switch themselves *on* and *off* as p&s and need shutters that are in fact same electronic-mechanical shutters than those in film cameras. Otherwise sensor will be always working while in fact they work only when shutter does open. Therefore a Nokton 1.2 must work flawlessly in M8 as it does in M7. Regards. Felix