iraf.net

I've got a psf generated by tiny tim(http://tinytim.stsci.edu/cgi-bin/tinytimweb.cgi). It is in fits format. Now I am trying to subtract an unwanted star using this psf. Other than the task substar, is there anything else I can use? I don't want to use substar because there are several tasks I need to perform first. I need not use the psf generated by iraf as I've already got one.

There may be other packages which do this in some way but I am not aware of them. There is nothing to stop you from using something as basic as IMARITH or IMEXAM. However you would then be responsible for getting your PSF to the right pixel sampling (adjust the center to the appropriate subpixel and the pixel scale) and the right intensity scaling. All this is perfectly doable but requires learning some tasks for doing the matching. The actual subtraction of a smaller image from a larger one would involve some fairly simple steps of copying out a raster from the science image, doing the subtraction, and then pasting the subraster back into the image. This can be done with IMCOPY.Frank ValdesAnother thought, which I've not explored, is that artdata.mkobject has some good features for adding stars, including from a template image. It does not do subtraction but ... it might just work to first negate the PSF image. The problem might be if it needs to do things with magnitudes. If you try this and find that it works it would be nice to let us know. Adding a subtraction option would be a nice feature (someday).