Lightproof comparison test circle

This is meant to test how lightproof different filaments are. In my design of old camera cartridges and various other film related devices, I've found different brands pass more or less light than others. I've even had different batches from the same brand vary.

Print this at .05mm layer height, 100 percent infill. The center is .1mm thick and it gets thicker at .05mm increments towrds the edges. Once you have printed this out in the filaments you want to compare, hold the samples up to a bright light source. You should be able to see light through the center, but each step should give you an idea of how your filaments compare to each other.

In my experience, black ABS is the king of light proof. I stumbled on a metal filled PLA that was great too (unknown maker) and I tried with others and they were pretty bad. Some silver filaments are OK. PETG has been the worst in my experiments, though I didn't explore it much since ABS worked so well.