One thing I always tell my clients is that some cropping may occur when they print from digital files. Unless the original digital image is cropped by your photographer or by you to fit a specific print size, digital files are not be formatted to “fit” any standard print size. Here is why:
One of the properties of a digital image is its dimension in pixels – length and width. My camera is an 18-megapixel camera and records digital files that are 5184 pixels long and 3456 pixels wide. Its ratio of length to width is 3:2, which means that digital files can make 3 by 2; 6 by 4; 12 by 8, 24 by 16 prints without cropping (in other words, there is no cropping as long as the original ratio is preserved). Every camera is different in regards to the length-width ratio of the images it records, there is no set standard.
The image below is straight out of camera without any cropping, it has a 3:2 length to width ratio.
Now, let’s see what happens if we use this digital file to make a 5 by 7 print. The shaded area below represents the part of the original image will be cropped out. The “long” side of the resulting print will be slightly cropped. The composition of the final print will not be as pleasing as the original because the child’s sweater is too close to the print border, but no important part of the image will be lost due to cropping.
Cropping will be even more substantial if we choose to make an 8*10 (or a 16*20) print. Unfortunately, this kind of cropping is unacceptable as a significant part of the main subject in the photograph is going to be lost due to cropping.
I usually recommend that if my clients receive digital files from me, they should check how their images will be cropped before printing. Most online and in-store printers give “previews” of how a printed image will look and have tools that allow customers to recompose their images for printing.
As a photographer, I usually compose my shots with a little extra “space” on all sides so that no important part of the image is lost later due to cropping for print.