These days when print is so competitive, printers need to be able to utilize technology to make them stand out from their competition. If this can be done without having to invest in new digital printing technologies or the very latest offset presses, and instead to be able to use the equipment they already have it is a real benefit. If this new technology can allow them to save money, improve productivity and enhance quality then it is surely worth evaluating. What I am covering in this article is a technology in improving the quality of printing without a significant investment that I believe can allow a printer to significantly improve their competitiveness.

Sometimes in terms of quality we believe we may have reached the limit of how far we can go, but then something new comes along that changes how we see things. One of these critical areas of quality concerns the way we handle color screening, and many people feel we have reached the limit in the way this can be improved. Developments in color screening have been progressing for years. As we moved from conventional photographic screens to digital screening we first moved from rational tangent color screening angles to irrational screening that allowed us to nearly match the traditional screening angles we were using in analog screening. One of the first problems in this was getting round the early patents in irrational screening. Once this happened major developments took place utilizing the power of the computer to optimize screen angles to improve color quality. Despite this we still had significant color problems in areas of color shifts, moiré or screen clashes that produced visible artefacts in the color images. We also had problems in handling flat tints and vignettes where images appeared grainy or lacked smooth transitions. In the areas of highlights and solids we lost detail as the rosettes filled in or disappeared as ink fill in occurred. We also had increasing difficulty printing with conventional digital screening (AM) of handling higher screen values to get better image quality.

Major developments in screening took place to try to get around these problems and new approaches to screening came about. The major one of these was FM (Frequency Modulated screening). This did away with rosettes and instead used what appeared to be a random approach of laying down very small single sized dots. Many suppliers offered FM screening under different names, perhaps the best known of these being Staccato from Kodak. This is offered in different formats depending upon the dot size, with the smallest dot being 10 micron (Staccato 10). While FM screening largely eliminated screening artefacts in continuous tone images, it had other problems these mainly being in flat tints being very noisy. Printing of FM screening could also be difficult require very controlled conditions particularly where very small dots were being used.