Pentax on Tuesday served both the very high and very low ends of its audience with more details on its first true medium-format digital camera as well as two special editions of its mainstream digital SLRs. Teased as early as 2007, the 645 Digital (shown) is now set to be the company's sharpest-ever camera and should produce at least a 30-megapixel image. It should also accept any of the film-ba
