My recollection is that the index of refraction for the nitrate film base is closer to the index of refraction of gelatin than is the acetate base. If you ever get a chance to see an original nitrate print projected--and you probably never will--you might notice warmer tones than with acetate. This applies to both B & W and color. There is a cult of nitrate worshipers in Hollywood. It was rumored--I have no idea if it was true--that when Spielberg's beach house burnt down years ago it was because he was storing nitrate prints in it.
Many Technicolor dye-transfer prints were done on acetate base beginning in the 1950's, as were "The Godfather" films I and II. I will stand by my support for the superiority of dye-transfer prints over chromogenic prints. I assume many of the EK professionals have seen Technicolor Dye Transfer releases. Is GEH licensed to project nitrate? I would love to hear from the experts.
Cinema is a great art. Just like painting it is better to see the original than to see a copy. Nitrate prints, however, are becoming more rare than Rembrandt prints.