Need some help masking stars in embedded nebulosity

[astrovienna]

Below are linear Ha and OIII images of M27.  During the linear stage, I'd like to do some deconvolution on the nebula with an extracted PSF, but I want to mask out the stars.  I can't manage to create a star mask that includes the embedded stars without the nebula.  Any tips?

https://dl.dropboxusercontent.com/u/58468743/M27Ha_OIII_Linear.zip

Thanks.

Kevin

[pfile]

one way to do it is multiple HDRMultiscaleTransforms on a copy of the L, at scale 2, then clip the image with HT to get rid of the nebula and use starmask. or you might be able to make the clipped L into a starmask by further smoothing and clipping, but beware faint structures left over.

rob

[msmythers]

Kevin

You might try a structure mask. In the attached image I used the Ha image. First used masked stretch with the settings shown. This gives a good image develop the mask from. Next clone the stretched image, this is for the star alignment reference image. Use the settings shown in star alignment. Apply the star alignment to your original stretched image. You now have the structure mask. Last apply some convolution to soften the star edges. These setting you can play with to see what works best for your deconvolution star masking.


Mike

[msmythers]

Kevin

Along the same line as with masked stretch you can use autohistogram. You might need to play with the settings a little but I like the results a little better.


Mike