A Study on the effects of dot gain, print contrast and tone reproduction as it relates to increased solid ink density on stochastically screened images versus conventionally screened images

Through the evolution of technology both print and process have become more predictable and reliable. As a result, innovations in the press and plate coating technologies along with imaging software technologies have challenged the way we view print. With lithography being the predominant printing process, printers now have to find ways to differentiate themselves from others especially in the color reproduction arena. For years, traditional halftoning methods have reproduced original continuous tone images with success. Today, however, the once accepted rosette is now being challenged by a new technology that does away with conventional screen rulings and dot patterns. This new technology called Stochastic Screening, offers many benefits and is loudly touted by its champions. Tone reproduction whether it be through conventional screening methods or stochastic screening methods is influenced by all parameters in the printing process. In this study, the effects of inking on dot gain and print contrast were studied. A test form was developed to test the prediction that stochastically screened images will perform equally or better than conventionally screened images under normal and increased inking conditions. Evaluation of the test results shows that conventionally screened images actually performed better than stochastically screened images. Stochastic images actually experienced increased dot gain and loss of print contrast in the 48% and 70% tint areas under normal and increased inking conditions. Although stochastic images had less of a performance, the images appeared to have less variation throughout the run. At the height of implementation, it is not likely that stochastic screening will become the standard for industry because there are many unanswered questions that still surround this new technology. It is also obvious that implementation of this new technology is bound to be limited by the challenges of controlling a wide variety of equipment across industry, as well as the need to control the plating and printing processes themselves