Large format cameras can produce amazing shots, but are a bit too bulky to be practical. Medium format is a different story, as [Wenting] demonstrates with his Sitina B220M — an open-source digital back for the Mamiya Super 23 camera using a full-frame Kodak CCD.“Digital back” just means he’s replacing the rear of an existing film camera in order to put a sensor where said film used to live. The sensor is a 22 Megapixel Kodak KAF-22000CE, which measures in at a very respectable 38.8 mm by 50 mm. That’s only a touch smaller than the rolls of 120 the camera was designed for, whose large dimension was 56 mm. How much was exposed at a time was determined by the back you put on the camera, but would never have been below 41.5 mm. Again, the CCD is pretty close.With Mamiya covering the optics, [Wenting] could focus on the digital end. He’s got a Xilinx Zynq 7010 running the show, making use of both that SoC’s Cortex-A9 cores and its built-in FPGA. There’s some decent info on how that works in the build video embedded below, if you don’t want to dig into the code at the GitLab repository above. The photos look great, and start at 8:25.[Wenting] has been around the bush with FPGAs before. Not least in his e-ink monitor project, but also with the last iteration of his mirror-less digital camera. This version is perhaps less ambitious, being merely a digital back and not the whole enchilada, but it solves some design issues he had on the “camera” part while he focuses on the “digital” for now.