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The search for those elusive pixels

By Darek Johnson

To print or not to print, that is the question. Touching the start-print button is based upon knowing if the file image is ready to print, meaning that it’s been through your series of prechecks – preflight, proof, custom settings, media and ink profile, and surely more. Before this, however, you’ve had to determine if the image has the number of pixels – resolution – needed to produce a print that will satisfy your customer (because customer choices often differ from those of the print producer).
In many occurrences, it’s not viewing distance that determines the final resolution/pixel count, but a customer’s concept of what is acceptable.
The viewing-distance line of reasoning must have begun with George Eastman’s first photo enlargement, but, in the digital age, an enlargement process is often accompanied by the digital printmaker’s arch-enemy: a desaturated and grainy image.
Lack of color saturation can cause an originally brilliant graphic to appear colorless. Further, such an enlarged, but thinned-out image may also produce stair-stepped jaggies, artifacts and more.
The following paragraphs discuss this one area of large-format graphics: how to get more pixels – saturation and, therefore, color – when the original file lacks the necessary pixels.
The best way, of course, is to create the original file at the final image size, with your desired pixel count selected. Unfortunately, not all software will do this. A second method is to calculate and select an original ppi count that matches your desired output. Method three is potluck – take what your print-buying customer sends, and try to make it work.