Is low contrast a characteristic of diffusion heads? Or am I doing something wrong? I'm printing for the first time with a diffusion head (Beseler universal 45), and finding that negatives that printed beautifully with a #3 Ilford filter (on Forte paper with a cold head) look dull and flat even with a #4 on the Beseler. I know, I know--I shoulda tried it with a 5. And I will.