Photographers routinely talk about four digital camera formats: medium format, full-frame, APS-C, and Micro Four Thirds. While there are technically two different medium-format image sensor sizes, and APS-C can mean slightly different things to various manufacturers, those are the “big four,” and they encompass basically every modern interchangeable-lens digital camera. But what about APS-H? That was definitely a digital camera format, so where did it go?
