I've been looking around at forlarge format digital cameras, i can't find much on large format digital camera, but they always seem to point at these thingies called 'digital camera backs'. But the information on these things has always been a bit sketchy. What is this? :scratch: Is this a camera itself, is this something you mount on a Large Format camera? How does this work? Any input would be greatly appreciated!! No, i can't even dream to afford to buy these at $20,000 - but I am curious of what they are and how they work.