Ballard wrote:
Hi bwa
Thanks for viewing the image of M57 and for the comment. The second image was my goal and was the more difficult image to process due to the large difference in brightness of the ring nebula center and the outer halo. I had to mask off everything in the HA image except the outer halo before adding it to the red channel to keep the Ha from dominating the image everywhere. Below is just the Ha image without any masking.
Up to this point I've never really considered M57 having a whole lot of Ha response and I've imaged it several times in narrowband as well as LRGB.