noise

Definition: Unwanted signals or disturbances in a system that tend to reduce the amount of information being recorded or transmitted. * In scanners: may be caused by electrical disturbance, mechanical instability. * In digital cameras: may be caused by thermodynamic fluctuations (heat) causing disturbances in the minute currents generated by the CCDs or CMOS sensors. No noise can be bad news Noise, despite its perjorative overtones, is not necessarily always a bad thing: some noise added to e.g. a smooth gradient can help prevent banding caused by unevenness of printing, particularly where the printer head runs parallel to the band of colour. Noise in a digital image prevents it from looking too artificially smooth. A few moles and pimples on Lara Croft would make her more real.

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