On the following page you can try out how the blend modes work with different colors:
https://naturfotografen-forum.de/?page=dtblend
I once was shown something quite like that, but i never found it when i searched later, so when i a few years ago tried to understand what the blending modes really do, I wrote this playground.
On Saturday, during cleanup, i found it again, and instead of throwing it away like some other things in that directory i dusted it off, added the subtract version of the JzCzHz blend modes, and removed a few profanities from the source code.
That comment about me email habits is still true. Even though iām not a regular here, you might find it easier to reach me here than through mail.