This is what the original looked like after stacking 15 light frames (3 min subs) with 5 dark frames in Siril. You can barely make out the red portion of the nebula.
Once I had it processed in Photoshop, I exported a tif and used StarNet++ to remove the stars so I could further process the nebula without affecting the the color of the stars. I use the stand-along version of StarNet++ and followed these instructions I found on CloudyNights to install it on my MacBook. Below is the starless version after removing all the stars.
I then opened up the starless version in Photoshop and layered it on top of the processed layer. I adjusted the starless layer opacity until I liked how it looked. The results are below with the combined starless (layered) and processed final version.
