The first video is one of the first things I made this semester in my Image Making class. It's a strip of clear 16mm leader with about ten seconds of thread sewn through each frame; every two seconds (every 48 frames) I switched from just thread to thread and sequins, one sequin per frame. This effectively created (as you can see) one giant sequin flashing different colors for a couple seconds.
The second video is a rayogram onto color positive film stock. I took the unexposed film and held the strip of sequins against it, with a light table below. By turning on the light table for a second or two the film was exposed, light shining through the sequined film strip, and an image was created that roughly (really roughly) approximated the first embroidered strip of film. My group and I also played with a bunch of filters laid on the light table, which is where all those crazy colors come from.