Words leave me at the moment. Setting levels in photoshop or gimp.
I took a snap shot of the neg on the light box but it was crappy and scanning the negative with full color range worked better and still demonstrated what I'm getting at. (Excuse the crappy pic, was a holga shot, APX in diafine - not a good combination and especially not with a fixed shutter/aperture camera. I dont have any good sounding excuses for the skills of the photographer. )
I've seen some dynamic range squishing with diafine that may have been overagitation (though that usually results in very thin negatives) but I got good mid tones in the negative - the neg looked ok on density to hold it up to the light, but everything scanned at middle grey. The Delta-3200 I shot in the holga came out like an grey lithograph.
My apologies for posting a holga shot in the Leica forum as well. 🙂