I really enjoy this format proportion. The 3:1 ratio can be quite difficult to create visual composition within, but sometimes it is the best image aspect ratio to work with. Panoramics can be horizontal or vertical. One of the great strengths of scanner photography is the ability to quickly and easily format your image ratio to fit the subject material. One the scanner these images start out at 2" by 6" to about 3" by 9". Most are scanned at 600 dpi.