Fun with layer masks

Once I started playing around with the layer masks for the H-alpha images below I just couldn't stop. I had a pretty decent H-alpha luminance image, so all I needed was a good RGB image to combine. After digging through all the images I have taken in the past few months, I found some 10-second M42 images taken in October with the unmodified Rebel XT. Using the layer mask in Photoshop I combined the short exposure image with a 180-second image taken in December with the modified camera (both resulting from many exposures stacked & aligned of course). The images taken at different times were not quite lined up so the "translate, scale & rotate" function in ImagesPlus was needed. The resulting image was then split into red, blue and green channels. Then it was combined with the luminance H-alpha image below. Again, the images didn't quite line up and needed some alignment. Slowly but surely I am starting to get a handle on all this processing stuff.