Pre-Press- color resolution ( Pixel depth )

Colour resolution (or pixel depth) refers to the software’s ability to record

colour differences. It has nothing to do with the resolution of area-related

detail. The relationship between the number of grey levels or colours that

a pixel can represent and the number of bits or bytes of computer memory

needed to store it is listed given below. The minimum requirement is

eight bits per colour (one byte), but often scanners are advertised as being

10-, 12- or even 16-bits per colour.

Colour resolution: bits per pixel

1 bit per pixel = black or white

8 bits per pixel = 256 shades or colours

24 bits per pixel = 256 red 256 blue 256 green = 16.7 million colours

each extra bit doubles the number of tones or shades that can be expressed

the software convention is an 8-bit environment

10- or 12-bit scanners = redundancy of bits for tone transformations

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