What Does DPI Mean in Photoshop?

DPI doesn't affect how cameras actually take pictures.

DPI stands for "dots per inch," and it is a standard of measurement used in digital photography. It has the same meaning in Photoshop as in other graphic design programs.

Picture Quality

For mere viewing purposes, DPI should not overtly affect picture quality. A photo can be set for 30 or 300 and should look the same. Changing pixel counts actually alters the onscreen quality of an image more. A pixel is the smallest unit of color in a picture, so as long as it stays constant, changing the DPI will be inconsequential.

Print Quality

DPI affects how a digital photo prints. A lower DPI value leads to a lower-quality photo coming out of a printer. This is mostly reflected in the size of the picture. Higher DPI numbers will shrink the printed result. Lower DPI values will enlarge it, sometimes to a point where the printout looks grainy.

Uses in Publishing

Print quality and DPI are crucial in the world of print-on-demand publishing. Publishing websites require certain DPI values. If a graphic designer doesn't specify the correct value in Photoshop before saving the file as a .jpeg or .pdf, the resulting image will be distorted.

References

• All About Digital Photos: The Myth of DPI
• Lulu: Mandatory Requirements for Distribution

Resources

• Adobe: Photoshop Help and Support