Resolution is one primary concern when designing a file for printing. Using too low of a resolution can degrade an image and make the final printed product look blurry. Starting off with a low resolution image often leads to delayed production and headaches further down the process. However, too high of a resolution leads to bloated file sizes and increased time spent uploading and downloading assets.The preferred resolution for any printed image lies somewhere in the middle – 300 PPI.
What is PPI?
PPI, or pixels per inch, is the most common metric for measuring image resolution when printing digital files. As the name suggests, PPI refers to the number of pixels that would be printed in a 1 inch line. For example, an image that is 1 square inch would contain 90,000 pixels when printed. The higher the PPI, the more densely packed the pixels will be, leading to a higher clarity image.
Why 300 PPI?
Any image printed at below 300 pixels per inch might appear to be blocky, blurry, or flat-out pixelated. That’s because each individual pixel will be large enough for the human eye to perceive. 300 is that magic number where each pixel is small enough to go unnoticed without a magnifying glass. Consequently, images printed at above 300 PPI won’t look any noticeably different or clearer, making the excess file size unnecessary.
How can I make sure my images print clearly?
The first step is to set your design program to 300 PPI before creating your file. In Photoshop, the default resolution is 72 PPI, well below our magic number of 300. Increasing the PPI after the design is completed, or “upconverting”, won’t change how the file is printed. You should also consider the resolution source images you use. Don’t get too attached to an image, especially if it falls short of the 300 PPI line. Plenty of high resolution images are online, and settling for a low-res picture all but guarantees a low quality print.
Calitho is a commercial printer and visual communications company serving the San Francisco Bay Area and beyond. Let us help with your next printing project by requesting a quote today.