Archived posting to the Leica Users Group, 2000/07/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Art, You are correct. Over exposure and underdevelopment is compression. It pulls the bright highlight and the deep shadow closer together. The overexposure lets the deep shadows find a few silver halide molecules to expose and the under development keeps the bright highlights from blocking because of the overexposure. Reducing contrast. Flattening out the gamma curve. Under exposure and over development is expansion. It spreads out the tonal range and makes the dark grays more black and the light grays more white. Just the opposite physics of compression. Increasing contrast. Steepening the gamma curve. Jim At 10:05 AM 7/25/00 -0400, Peterson Arthur G NSSC wrote: > >Just a quick question from an ignoramus who doesn't develop his own stuff. >You say that overexposing and underdeveloping increases contrast. > >I had long understood that underexposing and overdeveloping increases >contrast. And somewhere, somehow (I can't recall and can't explain it), I >had gotten the impression that, conversely, overexposing and underdeveloping >rather decreases contrast. Did you misstate this, or has my impression just >plain been wrong? > >Thanks in advance for the answer, > >Art Peterson