A Lesson in Aspect Ratios

Family photos are intimidating for so many reasons. The research that goes into finding a photographer you like; the wrangling of the kids; the location choices and wardrobe selections, and of course, the dreaded “what do I do with my arms” question. You think that once the shoot happens, the hard part is over and you can just relax. And you do relax, until your photographer asks you to choose what size photos you want. Then your brain freezes and you can only think of the most popular sizes. “Uh, 8×10.” So you get the 8×10’s and hang them on your walls, but did you get the best bang for the buck? Would 8×12″ have been better? What’s the difference between those two print sizes and how do they convert to aspect ratios? What are aspect ratios? What is the benefit of choosing one size over the other?


Richmond family photographer

Aspect ratios can be confusing even for photographers, so I don’t expect clients to be able to differentiate between the values of 16×20″ vs. 16×24″ prints. Here’s the skinny:

Most SLR cameras (with interchangeable lenses) shoot in a 3:2 aspect ratio, which is a ratio based off of 35mm film, where each frame is 36 millimeters long x 24 millimeters wide. If you divide 36 (the long side) and 24 (the short side) both by 12, you get 3 and 2, or a 3:2 ratio. That 3:2 ratio translates to real life to mean that when you print a 4×6″ photo, you’re getting the whole image, as it was taken by the camera. It’s not cropped on one side or the other. In order to continue to print the whole image as we scale up to bigger sizes, we need to break out the multiplication tables.

maternity photographer

If you multiply 4 and 6 (the two sides of a 4×6″ image) by 2, you get 8 and 12, or an 8×12″ photo. Multiply 4×6″ by 3 and you have a 12×18″ photo, which isn’t considered a “standard” print size, but would follow the same ratio and get the full image on the paper. Continuing to multiply up gets you 16×24″, 20×30″, and 24×36″. It means that the long side of the photo is 1.5 times as long as the short side, and nothing gets cut off.

Lifestyle photography

Conversely, if you look at 5×7″, 8×10″ or 11×14″ photos, whose ratios are shorter and fatter than the above, you’ll have to cut off some of the image in order to fit it on the paper. If you’re trying to fit a particular frame, this might make sense, but if not, then cutting off the photo might mean losing something important to the image, so going with 8×12″ instead of 8×10″ might be the right way to go.

Another factor to consider is whether the image is vertical or horizontal. Horizontal photos look better in 2:3 ratio because your eyes naturally scan left to right. However, vertical photos tend to look better cropped, because your eyes don’t like to look up and down as much as like to look side to side. If your eyes can view the whole image without having to scan up and down, they’ll be happier for it. So if you’re definitely considering the cropped formats (5×7, 8×10, 11×14, 16×20), you might look first at your vertical images to see which would look best.

A lesson in aspect ratios

Fun fact: most camera phones shoot 16:9 format, which is longer and thinner than 4×6″. If you’re printing phone pictures, you’ll have to decide between cutting off the short sides, or adding white bars to the long sides in order to get the whole picture on the paper.

If you don’t know about aspect ratios, now you know! I hope this will help with your planning as you prepare for your photo session.

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