»Many people seem to get hung up on the DPI (dots per inch) or PPI (pixels per inch) setting within a digital photo as a measure of the quality of those photos. To set the record straight, the DPI/PPI setting within a digital photo has NOTHING to do with digital image quality! The resolution of a digital image is its pixels (usually expressed as megapixels).
The PPI of a paper print IS a measure of quality (of the paper print, not of the digital photo) – but it has nothing (in real world terms) to do with the DPI/PPI setting within the photo.«
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