All of the information of a negative is between film base plus fog (fb+f) and max. density, and in an *optimally exposed and developed* negative, fb+f is pure black, and max. density is pure white. All you need to make this theory work is carefully calibrate your whole system. Then you more or less work according to the zone system. One problem when trying this with 35 mm or MF that there are many different photos on one film, usually with different lighting situations (some where the contrast between shadows and highlights is just a few stops, some where it's more than the film can handle). The other problem (with any format) ist that the film (and the human eye) can handle more contrast than the paper. So you might find that quite frequently, you have to sacrifice either the shadows or the highlights. There, the system breaks down.(posted 8942 days ago)That destructive comment given, use that method as a starting point. If the idea were nonsense, proof sheets would be useless, as each print would need its particular exposure.