Most people think of “night vision” as those green glow images of commandos from old spy movies and the covers of Tom Clancy books. That’s not wrong, but it’s only half the story.

Night vision and thermal vision both let us see when our eyes can’t, but they do it in completely different ways. One amplifies what little light there is. The other ignores “seeing” with light entirely and reveals the invisible world of heat and the lack thereof.

READ MORE: Seeing the Unseeable – American Handgunner