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Xara X. Imagesetting

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Imagesetting refers to printing your image from an imagesetting device to produce film that will be used to create commercial printing plates for printing your job on a commercial printing press.

In this section will will look inside the other two tabbed sections in the Print Options dialog: Imagesetting and Separations.

Xara can add a variety of Printer's Marks to your file when the Output Printer's Marks option is checked. By default the marks (shown on the left) that are checked are selected and included on the film. These marks will be explained in a few moments.

Print Film These options are used if you are preparing a file to be output as lithographic film to be used in turn to create printing plates. Emulsion Down (referred to also as emulsion side down) outputs the film with the coated side (the emulsion side) on the bottom so when it is placed over the photosensitive printing plate, the emulsion side of the film, into which the image is burned, is in close contact with the printing plate. Occasionally a service bureau or printer will request film emulsion side up, in which case, you would uncheck this option. This is the case when duplicating film (emulsion to emulsion).

Negative Film can be either positive (black images on clear film) or negative (clear images on black). Most prepress houses and service bureaus will require request film negatives, right reading, emulsion side down.

NOTE: On some occasions a prepress house or service bureau may request film that is right reading, emulsion side up. Right reading refers to the side of the negative that reflects the image and or text as it will appear when printed. The emulsion is usually on the wrong reading side. Sometimes the service bureau intends to duplicate your film, perhaps so a stripper can splice in some other negative images and then create a new master sheet of film. In this case the stripper will be contacting the film emulsion to emulsion.

Always Overprint Black Check with your printer or prepress house before making this selection. Overprinting black can solve some trapping problems. In images that have heavy amounts of solid black areas, you should  uncheck this option.

NOTE: Printers Marks are printed beyond the trim edges of the printed page. Hence if you are printing an 8 1/2 by 11 inch sheet of paper (after trim), in order to include Printer's Marks, you need to print on a larger sheet of print stock, usually about 9 1/2 by 12 inches. You can preview these printer's marks on your desktop printer by printing an 9 1/2 by 12 inch page at 89% or by selecting Best Fit. Printers marks will not appear if you print your document as a bitmap.

When your output film separations, and select Add Printer's Marks, Xara includes these marks on all sheets of film. As the marks appear on the same place on each piece of film, and subsequently on the printing plates, the printer can use these marks to endure the printed output is in registration and the colors match those of the image.

a. Plate information which includes the file name, date and time of printing, and individual plate color name, (magenta in this case).

b. Registration Stars are used by the printer to register the four printing plates. Each sheet of film has the same marks in exactly the same position. These registration marks ensure precise registration.

c. Crop Marks are used by the printer to trim the printed sheets.

d. Registration Stars are another method of ensuring precise registration of the four plates when on press.

e. Grayscale Bar provides a calibration device the pressperson can use to determine the correct amount of light and dark values in the printed output.

f. Progressive Color Bars This image is composed of colors from all four printing plates and can be used by the printer to adjust the intensity of color to match the original image. In reality, only the magenta components of these bars would appear on this page. A page called a "composite" will contain all four plates and will appear as the final page will appear when printed.

Printers (persons who produce printed output from a printing press and not the press itself) also produce what is known in printing as a "progressive". This is a series of on press proofs showing each plate alone, and in combinations. The magenta page might look something like the illustration above. The pressman and client review this progressive and use it to determine if all the plates are printing properly or if one or more of the ink densities needs to be increased or decreased. The pressman can also read the density of the color bars and grayscale bars with an electronic device called a Densitometer, which compares the density of the printed color bars with settings in the computer. Using this information, she/he can adjust the ink flow to fine tune the printed output. A good pressperson is worth his/her weight in gold.