Jason Wong

Hi, I'm trying to figure out how to use Photoshop for scientific image
analysis purposes. I'm doing some neuroscience research, and what I
need to analyze is the intensity in certain brain regions created by a
specific staining technique. So what I was thinking of doing is using
the square marquee of Fixed Size to anaylze a square from Region A, and
compare that to a same area in Region B. What confuses me the most is
if I do Image --> Histogram, the value for Mean seems to be inversly
proportional to the staining intensity. i.e., if the region is darkly
stained I get a small Mean value and vice versa.

Does anyone know what I'm talking about? Is there a specific formula I
would use in order to determin the relative optical density of a certain
region? Any help would be greatly appreciated!

-- Jason