Quantitating spots on an autorad

Posted by Castora, Frank J. on Jul 18, 2013; 4:18pm
URL: http://imagej.273.s1.nabble.com/Quantitating-spots-on-an-autorad-tp5004024.html

Please HELP!  I have spent hours and days trying to quantitate round spots of varying darkness on autorads, with no success.  When I draw a circle of a certain size, and use it to get the density of the lighter background of my autorad, I measure an integrated density that is, say, 1,000,000.  Then, when I move that circle to enclose a light gray spot, I get a SMALLER integrated density, say 550,000, and then when I move that circle to a dark black spot, I get an even smaller integrated density, say 130,000.  This makes no sense to me.  I have tried all sorts of combinations of image modifications and analyze modifications to no avail.  It seems like I must reverse some parameter but I can't determine how to do that.  I can't get over the fact that this should be easy to do.  Autorad, light spot, dark spot.  Light spot - lower density, dark spot- higher density.

I have tried the sample gel that can be downloaded.  There you use the rectangular tool to identify lanes and you get peaks and assign a baseline and so forth.  I see how that works and it does in fact give higher values for larger peaks (darker bands) but I am convinced there is another way that uses the circular tool that would be most appropriate for analyzing circlular spots on an autorad.

Anyone have any suggestions?

Frank J. Castora, Ph.D.
Professor of Biochemistry
Department of Physiological Sciences
Eastern Virginia Medical School
700 W. Olney Road
Norfolk, VA 23507
[hidden email]<mailto:[hidden email]>


Frank J. Castora, Ph.D.
Professor of Biochemistry
Department of Physiological Sciences
Eastern Virginia Medical School
700 W. Olney Road
Norfolk, VA 23507


--
ImageJ mailing list: http://imagej.nih.gov/ij/list.html