Getting down to the wire here and need to finish films fast while keeping SOME kind of thread. I went back to my list of true experiments and tests and picked out this "scratch film". I remembered I had done rain before in another film using scratches from a dirty film texture I had. But being that that was a ready-made live action clip of film scratches, I couldn't control the scratches themselves.
So I took a thin fabric marker that had run out of ink made scratches on blank pieces of paper.
When scanned, it just looked like a blank white sheet of paper with barely noticable marks:
So I added a Threshold filter, which basically crushes all colors into pure blacks and whites and ramped up the black Levels:
I did about 50 pages worth of scratches in various shapes to look like sheets of rain, ripples, drips and drops, etc:
This is good for a first test. It's a great, easy and fast way to create analog rain or moving scratch textures without CGI. If I ever expanded on this technique, I'd want to try a more painterly approach to the coloring as opposed to tinting it overall with one or two colors.
Here are some finished stills from the film:
Thanks for reading!