Certainly not diagnostic images (Score 0)

These are certainly not diagnostic images. That doesn't mean that they're not useful. The color depth of grayscale film is 9 bits (at least this is what the human eye can distinguish). The resolution of a large sheet of film might only be 1024 x 4096. The color depth of 9 bits is difficult to reproduce consistently across the entire surface of phosphor tube. Most diagnostic images still use film.