Substract uneven background value from ROIs in image

Posted by Spongiforma squarepantsii on Aug 16, 2017; 8:16pm
URL: http://imagej.273.s1.nabble.com/Substract-uneven-background-value-from-ROIs-in-image-tp5019217.html

I have fluorescent images, with ROIs I detect (clusters, a few hundred in each image). However, the background fluorescence is very variable in the image. Some ROIs are surrounded by very little background, and some by a very intense background fluoresence. I would like to subtract a value for each ROI that best fits the background surrounding that particular ROI. How might I be able to do this?