Have you ever wondered how some film cameras just know what speed ISO (or ASA) film you’re loading into it? Well, have you ever noticed those black and silver squares on the side of the roll? That’s called DX Encoding and that’s how the camera knows what film you’re using.
This video from photographer Azriel Knight goes deep into the origins of DX Encoding. He talks about how it was created, how it works, and how it was received when it was first introduced. And, no, it’s nothing to do with Nikon’s 1.5x crop cameras.