Why is the resolution, or pixels-per-inch of digital cameras, so low? My Olympus Camedia C-5000 is only 144 ppi in TIFF format, and only 72 ppi in JPEG format, although the maximum image size is 2560 x 1920. When printed out, the files look a bit grainy, even the TIFFs, and after they have been resized to a smaller size too. When I scan in photos on my scanner, I always set the resolution to 300 ppi, which I think is the minimum resolution for good quality photos. So why aren't all digital cameras at least 200 or 300 ppi? What is the minimum adequate digital camera ppi for taking photos that are going to be converted into large posters, about 3 feet wide and tall?