When I was planning on taking video of the solar eclipse, one thing that had me worried was that with the high temps that day and the black bodied camera sitting in the hot August sunlight, there was a real good chance the camera would overheat and maybe trigger a thermal shutdown. So I needed some way to try to block the sunlight from striking the camera body directly.
I found a white plastic lid off of a bucket that looked like it would be the right size, so I used a 3 inch hole saw to cut a hole for the lens to fit through, and this seemed to do the job perfectly. Sure, kind of a kluge, but it did the job.