Practical, no doubt, but pretty unsporting, especially when it’s possible to cast custom lenses at home using silicone molds and epoxy resins. Possible, but not exactly easy, as [Zachary Tong ...

There was only one problem…she had no experience with the silicone molding process or epoxy ... a two-piece mold, into which [Gina] embedded two channels: one to inject the resin, and another ...