Can someone please help me with densitometry analysis for
immunohistochemistry? I am analyzing guinea pig hippocampal slices
that have been stained for the presynaptic marker SNAP-25. I want to
be able to compare the relative optical density between the different
hippocamapal regions. What I want to do is to draw a small square of
fixed size (say 50x50 pixels) and stick it in Region A. Then I want
to be able to find the relative optical density of that region, then
move my selection square to Region B and so on.
So far I've figured out how to make a square marquee of fixed size in
Photoshop 7, and I can also do Image --> Histogram to get some
information. What really confuses me is what the Mean values are. If
I put my selection square over a dark region, I get a small Mean value
but if I move it to somewhere light I get a large one! It just seems
counterintuitive.
Can Photoshop be used for what I want it to do? I just downloaded
ImageJ for the PC but am having the same confusion...Thanks!
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