20TB? What specifications are you scanning them at?
It depends, and I’m not sure exactly what you are asking, but typically Full aperture 4K, 16bit log or 32bit linear depending on the scanner, and when possible with an IR pass for the damage matte, that is stored in the Alpha Channel.
So, somewhere around 4300 x 3200 resolution, in ACES colour space, saved in .DPX format or .EXR
Some are done in other colourspaces, particularly when I haven’t been the person running the scanner.