Back in the 1800s, large format cameras were used to take portraits. These cameras used glass negatives that were 8 x 10 inches in size. When developing the negatives, photographers would make contact prints that were the same size as the negatives. This is why traditional portrait prints are still based on the 8 x 10 inch size for the paper, even as camera technologies have advanced. Photographers are advised to leave extra room around portraits when composing shots to allow for cropping images to fit the standard 8 x 10 ratio.