Why 8×10 eats the sides of a 4×6
4×6 is 3:2. 8×10 is 4:5. Those are different rectangles. To fill 8×10 paper, a lab keeps the short side and trims the long side. On a 6000×4000 file that is a 3200×4000 keep — 47% of the pixel area is discarded. The people at the left and right of a group photo are the first to go.
5×7 (5:7 ≈ 1:1.4) sits between 3:2 and 4:3, so both camera stills and phone stills lose a strip. Square frames take the center of either. ISO A-series paper is 1:√2 (about 1:1.414), close to 5:7, not to 3:2.
How to shoot if you know the frame
Leave space around the subject on the sides you expect to lose. For an 8×10 from a 3:2 body, compose a little loose on the long edge. For a square album from a phone, keep important detail out of the top and bottom. Then confirm with this preview before you order a set.
After you like the crop, check sharpness on the print checker — a heavy crop also lowers DPI.
Questions people actually ask
- What aspect ratio is a 5×7 print?
- 5:7, or 1:1.4. It is not 3:2 and not 4:3. Both camera and phone files are cropped to make a 5×7.
- Can I print without cropping?
- Yes: ask for a border, or pick a paper that matches the file (4×6 or 8×12 for 3:2; 6×8 for 4:3). Fit mode on the checker shows the DPI if the whole image is letterboxed.