click-to-click intensity substraction

[Wasserman]

Hi,

I was wondering if anyone knows of a script out there where I could click into a cell nucleus and then a cell body and have the intensity of the cell body in a specific channel be substracted from the nucleus. I would need to do this for multiple cells within an image and, therefore, the data would need to come out into some kind of list of the total intensity differences for all the cells counted.

Please let me know if you do (you'd be saving me hours of staring at a computer screen :D)

Thank you