Hello,
I've been mosaicking county-wide images from 1958 and 1937/8 for several counties in the Sacramento Valley. I've experienced the same problem.
My raster mosaic has pixel values ranging from 110 to 202. I'm wondering if I stretch the pixel range from 1 to 256 if I would get a better image. So far, I've just used the defaults in the color balance toolbox.
Did you find a way to get a better image? Also, what imagery are you mosaicking? My images are from USDA flights; seems they covered a lot of counties in those time frames.
Jonathan Mulder
Engineering Geologist
California Department of Water Resources
Red Bluff, CA