On the Hasselblad H system, the viewfinder setup is also modular. To match different digital back sensor sizes, Hasselblad uses interchangeable focusing screens in the viewfinder. The screen is changed to one designed for the sensor size you’re using, so the framing you see corresponds to the image area that back will capture. In other words, rather than relying on an electronic crop mask like some DSLRs, the H system matches framing through the appropriate viewfinder/focusing screen configuration.