Hi, How does one put a circular aperture on an image in order to measure flux within it?
For instance, if in a 2048x2048 fits image I wanted to use a circular aperture of size 11 pixels (diameter) and sum the counts, what is the best way to go? How do I collect the "background" by using a larger aperture (say 17) and excluding the earlier aperture (i.e. an annulus)? Cheers, -ashish Ashish Mahabal, Caltech Astronomy, Pasadena, CA 91125 http://www.astro.caltech.edu/~aam aam at astro.caltech.edu Do not try to bend the spoon. That's impossible. Instead, only try to realize the truth. _______________________________________________ Perldl mailing list [email protected] http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
