[David Prutchi] writes in to tell us about his recent experiments with building lenses for thermal imaging cameras, which to his knowledge is a first (at least as far as DIY hardware is concerned).

A thermal camera is a tool I have been wanting to add ... There is no screen, no memory card on which to store photos and videos, nor are there any hardware controls on the camera itself.

The elderly man with dementia was located in a field of thick brush off the side of a roadway about a quarter-mile from his home.