Pentax K-r Operating Manual page 343

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sRGB (standard RGB)
International standard of color space established by the IEC (International
Electrotechnical Commission). This is defined from color space for
computer monitors and is also used as the standard color space for Exif.
Vignetting
The picture edges are blackened when part of the light coming from the
subject is blocked by the hood or filter ring, or when the flash is partially
blocked by the lens.
White Balance
While shooting, color temperature is adjusted to match the light source so
that the subject appears to have the correct color.
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