I spent some time trying to figure out exactly how it was done so let see if I am correct:
1) Base colors in one layer 2) We have clipping mask filled pure black with opacity about 50% 3) We paint light areas with pure white 4) Where we need to erase to modify we pain it again with black 5) Not going to lie - on that step I got confused it for certain you either use blur tool where you feel fit or just simply use Gaussian blur filter with something like </= 10... But how did it turned white-to-transparent? I suppose at that step you changed layer mode to multiply?
Would be really-really nice of you if you could respond and correct me if I am wrong and especially explain 5th part more deeply. However if I am wrong and you do not feel like correcting simple “No” will do and I'll just try to figure it out on my own via more experimenting.
Do you happen to know if Illustrator can do masks like this, or will I have to export to Photoshop? I really wish you had a video of this, I want to learn how to do it. I've been doing more and more vectors, but they just don't seems to stand out.
I am seeing your procedure and it is very organized. However, I have a suggestion that might be fun for you to try.
You are using black for shadows, which is affecting your colors and removing vibrance. You can avoid that by sticking to one extra principle of painting; that being, warm light cast cold shadow and viceversa. So, here, we have low sunlight (an orange-yellow=warm) so, the shadow should be Blue/purple, set to multiply at at least 45%.
You can compliment that effect with gradients and filters after, but that is just mirrors and smokes, the real deal is what I just exaplained.