Raster Graphics - Resolution

Resolution

Raster graphics are resolution dependent. They cannot scale up to an arbitrary resolution without loss of apparent quality. This property contrasts with the capabilities of vector graphics, which easily scale up to the quality of the device rendering them. Raster graphics deal more practically than vector graphics with photographs and photo-realistic images, while vector graphics often serve better for typesetting or for graphic design. Modern computer-monitors typically display about 72 to 130 pixels per inch (PPI), and some modern consumer printers can resolve 2400 dots per inch (DPI) or more; determining the most appropriate image resolution for a given printer-resolution can pose difficulties, since printed output may have a greater level of detail than a viewer can discern on a monitor. Typically, a resolution of 150 to 300 pixel per inch works well for 4-color process (CMYK) printing.

However, for printing technologies that perform color mixing through dithering rather than through overprinting (virtually all home and office, inkjet and laser printers included), printer DPI and image PPI have a very different meaning, and this can be misleading. Because, through the dithering process, the printer builds a single image pixel out of several printer dots to increase color depth, the printer's DPI setting must be set far higher than the desired PPI to ensure sufficient color depth without sacrificing image resolution. Thus, for instance, printing an image at 250 PPI may actually require a printer setting of 1200 DPI.

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Famous quotes containing the word resolution:

    A resolution to avoid an evil is seldom framed till the evil is so far advanced as to make avoidance impossible.
    Thomas Hardy (1840–1928)

    Had I been less resolved to work, I would perhaps had made an effort to begin immediately. But since my resolution was formal and before twenty four hours, in the empty slots of the next day where everything fit so nicely because I was not yet there, it was better not to choose a night at which I was not well-disposed for a debut to which the following days proved, alas, no more propitious.... Unfortunately, the following day was not the exterior and vast day which I had feverishly awaited.
    Marcel Proust (1871–1922)

    Unfortunately, many things have been omitted which should have been recorded in our journal; for though we made it a rule to set down all our experiences therein, yet such a resolution is very hard to keep, for the important experience rarely allows us to remember such obligations, and so indifferent things get recorded, while that is frequently neglected. It is not easy to write in a journal what interests us at any time, because to write it is not what interests us.
    Henry David Thoreau (1817–1862)