iraf.net

Hi..
I am trying to obtain the skyvalue using fitsky. There is a bright source in the annulus region that I considered. So, I masked those pixels using fixpix task. The fixpix task created a new fits image. I used this new image as input to the fitsky task. The problem I find here is that, the values in the fitsky output file are exactly the same as the values I got when I used the original image. Can you help me identify where could the problem be.

Thanks,
Sravani

Without seeing the data before/after masking and your parameters, it is hard to say what might be happening. Note that some parameters such as fitskypars.annulus are specified in terms of "scale units" and not actually pixels. If I had to guess at this point I would say that you're confusing these values (see datapars.scale) and so you get the same answer because you're not actually measuring an annulus that overlays the modified pixels.

If that doesn't explain it please upload your data to the anonftp at ftp://iraf.noao.edu/pub and post your parameters (don't forget the psets like DATAPARS, e.g. "cl\$this->_split2($m[0]) dpar datapars fitskypars .....").