I like the high focus on "value" in this piece, and the "movement" from the left to near center [at the light source] was eye catching. Like all your compositions, very realistic use of the brush texture, and you made a good sue of the space. (It's a piece that makes you squint your eyes and try to absorb every last detail).
You might want to add a bit more in the top left corner. While there's a good display of value, it seems a bit lacking (I'm seeing bright stars elsewhere).
Seeing you did this on Photoshop is a pretty good thing. Looking at this piece, I never got the feeling that you just "Clicked Filter>Render>Clouds" or just abused Color Dodge the way an amateur would. I've noticed over ten different colors in this composition just by looking, and they were blended rather well.
I love it. the colors are great! and the detail is awesome too
When I do my nebulae, instead of (like in your tutorial) placing down a bunch of colors, I'll actually find a good, free (or one I took myself) stock photo and blur it using Gaussian blur until it is just a whole mass of colors, and then using the smudge tool and brush tool (set to linear dodge of course ) form the nebula out of there.
playing around with the blend modes also really makes it interesting, haha.
That's an interesting approach. I've always stayed away from using stock photos in my nebulae paintings. I wanted to show that I could create art with only my own resources. I think I've proved that well enough so I might do a couple more using cloud photos. Just to see what kinda things I can come up with. Thanks for the support, friend.