After printing Mathgrrl's Total Eclipse pendant (www.thingiverse.com/thing:2481857), I wanted to create a pinhole design. So I thought of just a blank insert with a pinhole. but that was dull. Videos show people uses colanders and I was wondering if the shape of the pinhole mattered.

Technically, there is a top and bottom with the edge slightly tilted inward. I can't tell with the physical print though.

Depending on which side is facing you, the outer row is concave, the inner row is convex and the center is cylindrical (we should get at least one good pinhole shadow). Otherwise the opposite is true. There is no wrong way!!

No guarantees of effectiveness but can't wait to find out together on August 21st.

Update: It worked awesome! when I first tried it, i thought the holes were too big and nothing was working. However, I had first tested it when the partial had just started so the crescent shape wasn't as present. I tried it again about a half hour before totality and it was wonderful. I took this pictures at that that time. note: the picture of the sun was taken with my iPhone with the eclipse glass "lens" placed over the camera's actual lens.

There is no significant difference between the convex and concave holes at least at this distance. more holes the better.