The Nikon D4 uses all 14 of its bits all the time except for those lost to digital white balance.
The Nikon D800E is at 14-bit device with all codes present except for those lost to digital white balance until the ISO knob gets to 3200. Then the gain of the analog amplifier stops increasing and the output of the ADC is shifted one bit to the left, giving thirteen bits of resolution. There is another one bit leftward shift and concomitant loss of resolution to 12 bits at ISO 6400.
The Sony RX-1 is never a 14-bit instrument. It starts at 13 bits at ISO 100, and loses another bit in two of the channels at ISO 6400.
The Sony NEX-7 starts out a 12-bit camera at ISO 100, is 11 bits at ISO 3200, and 10 bits at ISO 6400. The NEX-7 is specified as a 12-bit camera, but looks like a 14-bit camera to RawDigger.
Jim, what do you think the explanation is for the apparent inconsistency between the NEX 7’s 12 bit specs and the 14 bits seen in Raw Digger?
It could be a RawDigger problem. Sony advertizes the camera as 12 bits. The EXIF data in the raw files from the camera say 12 bits. Maybe RawDigger doesn’t look at the EXIF data and only at the camera model, and has the wrong bit-depth coded in.
The 13-bitness of the RX-1 appears to be Sony’s problem, however.
Jim