Pentax MZ-D

The Pentax MZ-D, also known by its internal code name of MR-52, was a prototype digital single-lens reflex camera from Pentax of Japan. It was announced at photokina in September 2000[1] and was demonstrated to the press at the Photo Marketing Association (PMA) show in January 2001.[2] In October 2001, Pentax cancelled the camera, stating "The cost of manufacturing the prototype SLR 6-megapixel digital camera meant it was not a viable product for our target market"[3]

The MZ-D was derived from the top-of-the-line Pentax film camera of the time, the MZ-S. To give space for the extra circuitry and battery power required for a digital camera, the MZ-D shape incorporated the size and shape of the MZ-S' optional battery booster and vertical grip. It also shared the Pentax K_AF2 lens mount. The MZ-D was to use the same 6 megapixel (3072×2048) full 135 film frame sized (24×36 mm) CCD (model FTF3020-C[4]) from Philips that was used by the Contax N Digital. The lack of success of that camera and the image quality problems it displayed suggest to some that Pentax may have had other reasons than cost to cancel the MZ-D project.
Michael Reichmann of The Luminous Landscape stated, "For whatever their reasons Pentax decided that they couldn't build a camera with this chip, while Contax decided to forge ahead. To save face? Possibly. We'll likely never know for sure"[5]

In 2003, Pentax released a different design 6 MP APS-C sensor size DSLR, the Pentax *istD.