In the process of producing a hard copy print of a digital file using digital writing technology, whether the marking engine makes an exposure (light or thermal) or a physical mark (dye/pigment transfer, mechanical energy), the printed image may not be a perfect rendering of the original digital file. For example, the target file may include a straight line; however, the printed line may show extraneous features, artifacts, in addition to the intended line. The underlying mechanism responsible for extraneous features in digitally written images are different for the various output technologies used to make the hard copy print. In some thermal systems, the symptom is “thermal smear”; in some inkjet systems, the symptom is “bleeding” or “feathering”; in electrophotography, the symptom may be “toner sprays”; and, in digital AgX, one such symptom is “fringing.” All of these symptoms have one characteristic in common: the edges migrate relative to the original digital image. We will examine factors that may affect line broadening in different imaging systems and show ISO 13660 line blur as a metric to quantify this phenomenon.