Unlike other medium-format DSLRs, which accept digital camera backs of different resolutions or even manufacturers, the 645D has a fixed-back design similar to smaller full-frame and APS-C DSLRs. The fixed back allows the 645D to be fully weather-sealed.
Awards
The 645D was awarded the Camera of the Year award at the Camera Grand Prix Japan 2011.[1] Pentax celebrated this with the release of a limited edition of the camera.[2]