PostScript, RIP, PREFLIGHT, Stochatic Screening

A programming language created by Adobe to optimize printing of text and graphics on film or paper. The language allows for multiple complex pages with text and graphics with over 300 commands for lines, shapes, fills, text and formatting. The language is a completely text explanation of the page

Raster Image Processor. A program or device used to analyze text, raster and vector images and generate each pixel or bit of memory, which in turn creates a large bitmap interpretation to be printed. The RIP creates halftones for all the photographs, and converts vector graphics to raster, which is assigned to bits to contain the image. The fonts are also ran through a process which formats the letterforms to vector art which is then converted to raster as well.

Preflight aids in making sure a document is setup correctly before sending it to print. It involves analyzing the graphics, colors, fonts, gradients, fills, trapping, and more. Many printers provide their own preflight sects their printing presses. Many times bleeds and crop marks very from printer to printer. Failure to flight checks a project before sending it to print could result in many problems. Preflight can save a lot of time, aggravation and money.

Stochastic Screening:
Stochastic Screening is a type of screening used in PostScript image setting. Its major advantage over conventional halftone screening is that it has eliminated the issues with moiré, and screen angles by using dots that are the same size with no fixed grid. The process is very similar to pointillism used in pen and ink drawing or painting. Stochastic, or FM screening has shown to provide better quality with its finer type and lines. It also has improved the look of images with crisp detail clarity.

While it does hoave its high points FM screening does have some problems. It has a high learning curve. Since there is a high dot gain the images turn out much darker. Many adjustments are necessary to get quality results. Skin tones have also been difficult to make even.

Frank J, Romano. Pocket Guide to Digital Prepress. Clifton Park, NY: Delmar, Cengage Learning, 1996.
Foundations of Electronic Production G322 UG . Week Six Online Lecture : 5 2010

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