Auto exposure
The CONTAX 645 can work in different auto exposure
modes. This is fully supported by the P back, which
communicates the equivalent film speed of the digital
back to the CONTAX 645 camera.
When capturing with auto exposure modes, expo-
sure times between 1/4000 sec. and 32 sec. can be
obtained. Please note that images captured with ex-
posure times longer than 60 sec. can be degraded
because of increased digital noise also depending on
the ISO setting. The auto exposure of the CONTAX 645
camera uses the ISO value set in the P back, or when
shooting tethered, in the Capture One application. The
ISO can be set to 50, 100, 200 400 or even 800.