Minolta PAGEPRO EX, Руководство пользователя

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Optimizing files for processing and printing
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In this table, the shaded area indicate that 200 ppi is typically the best
trade-off between image quality and file size. However, higher
resolutions (e.g., 250 to 300 ppi) may be needed for offset printing,
when quality is of the utmost importance, or for images containing
sharp diagonal lines.
To find the best image resolution for your purposes, make test prints
of some raster artwork at different resolutions. Start with a high-
resolution image (400 ppi) and save versions at progressively lower
resolutions, down to 100 ppi, using a pixel-editing application such as
Photoshop. Always save a copy of the original high-resolution
version in case you need to revert to it. The high-resolution data
cannot be recreated from a lower resolution version.
Print the files and examine the output. You will likely begin to see a
marked deterioration in output quality at resolutions below 200 ppi,
while above 200 ppi the improvement may be very subtle.
Raster images prepared for offset printing may need to be at higher
resolutions than needed for proofing on your printer.
100 ppi 200 ppi 300 ppi 400 ppi
Image resolution
Image
quality