Kodak advises the following file sizes and resolutions: The image resolution needs to be at least 640 x 480 pixels for a 4″ x 6″ print. The image resolution needs to be at least 1024 x 768 pixels for a 5″ x 7″ print. The image resolution needs to be at least 1536 × 1024 pixels for an 8″ x 10″ print.