Binh Danh uses the oldest photographic technique from the early 1800s, Daguerreotype. It’s an involved technique that uses a sheet of copper plated with silver and buffed to a mirror finish. Then, treated with some fumes, the plate becomes light sensitive. After exposing something on the plate, and here comes the good part, you use mercury vapor to bring out the resulting image. Then the light sensitivity needs to be removed, so that’s another chemical bath until it’s all finished and ready to be put on display somewhere.
Listen to his interview on NPR above, then go look at the work that Bind Danh has decided to continue doing documenting America’s beautiful National Parks.