Despite major GUI annoyances and a GUI that is extremely unfriendly to folks with mild-moderate vision problems, I'm (not having fun exactly) challenging myself to do a little scrapping in Affinity Photo instead of Photoshop. AP drives me batty; the stupid program insists on knowing what layer it thinks you should be on instead of letting you stay on the layer you're editing - so I'm always making my edits to the wrong layer, but it saves $$ if you can put up with the frustrations and don't do serious masking.

That said, here are my process notes for Robert Frost Stars < https://oscraps.com/community/media/day-10-robert-frost-stars.403020/ >. I bumbled onto an interesting complicated masking technique on YouTube <https://www.youtube.com/watch?v=j8jszUpmSM0> When I searched for it again using Google I found almost no other descriptions of this technique, but it's what made this LO possible.
(1) Used invert and reduced opacity B&W adjustment layers to create base layer from NLD paper 2. The sky of the new base layer was black, not really what I wanted.
(2) Converted a copy of (1) to a greyscale layer, inverted it and made a child clipping mask (not the same thing as regular mask), clipped that to dark blue FoxySquirrel paper (3) and set the blend mode of the child to erase. The child clipping mask knocks out the bottom of the Foxy Squirrel paper so the final BG shows the midnight blue from the top of the Foxy Squirrel paper but the whites and blues from the bottom of the NLD paper.

The process was complicated and a little buggy - specifically, the equivalent of "blend if" described in the You Tube vid did not work in this LO even though it worked in a test document I'd done earlier - and I had to do more testing to understand why why. As anyone who uses AP regularly knows, it's not easy to land the layer you want to clip in exactly the right place so it actually gets clipped. Turns out the buggy GUI sometimes absolutely refused to let me put my layer icon in the correct "drop zone" to form the child clipping mask, so my layer ended up as a regular mask instead and I couldn't spot the subtle differences in the vision-unfriendly GUI. There was no rhyme or reason as to why this happened. Fortunately, my guess is that I won't be needing all the capabilities of a child clipping blend-mode erase layer very often if I decide to do this again.

Anyway, if you use AP, it's worth watching the vid to see if this is something you might be interested in. I stayed at v1 b/c v2 is even more unfriendly for me and my vision issues, but I understand that in v2 they tried to fix some of those drop zone issues.