From Pixels to Paper: Print Resolution
A digital image is made of pixels, but a physical print is made of ink dots. The relationship between the two is defined by DPI (Dots Per Inch) or PPI (Pixels Per Inch). To achieve a high-quality, professional-looking print that doesn't look 'pixelated' or blurry, you must ensure your image has enough resolution for the desired print size.
The Standard Benchmarks
- 300 DPI: The gold standard for high-quality printing (magazines, photo books, small prints). At this resolution, the human eye cannot distinguish individual pixels from a normal reading distance.
- 240 DPI: Excellent quality, often used for larger gallery prints.
- 150 DPI: Acceptable for large posters or canvases that will be viewed from several feet away.
The Formula
To find the maximum print size, you divide the total pixel dimensions by your target DPI.
Print Size (inches) = Pixels / DPI
Where:
Pixels=
The width or height of your image in pixelsDPI=
Desired print density (usually 300)Viewing Distance and Resolution
The required DPI is actually a function of viewing distance. A giant billboard might only be printed at 15 or 30 DPI because people are viewing it from hundreds of feet away. From that distance, 15 DPI looks as sharp to our eyes as a 300 DPI photo held in our hands.