http://www.camera-pentax.jp/new2014apr/en/pc/
and http://www.us.ricoh-imaging.com/645z/
Very possibly using the new Sony 50MP CMOS sensor in 44 x 33mm, with the following key specifications:
High sensitivity ISO100 to ISO6400 (compared to max ISO 800 for most digital backs so far).
14 f-stops dynamic range
50 megapixel CMOS sensor – 44 x 33mm (68% larger than a 35mm sensor).
Responsive
