I have 5% vlt tinting film that I cut to fit my lenses. I did this 10 times for each lense so the film overlaps each time. The formula (vlt1 * vlt2)100 = vlt3 is used to calculate the new vlt of the glasses. mine would be (0.05^10)100 = 9.765625e-12% vlt or 0.000000000009765625% vlt.
Answers (2)
Cut two holes in a box and stick a piece of white paper inside. Tape foil over one hole and punch a pin through the foil. Now the sunlight shines through the pinhole and makes an image on the white paper and you can look through the other hole at the image on the paper. It's free, it works, and it's safe. There is no reason to invent something that you are not sure is going to work.