Photography Noise: How to Work It
By: Robert Machado (Yelo34)
Noise has been the "black beast" for digital photographers for a long time. Noise causes colored pixels that interfere with the purity of an image. However, nowadays with improved technology noise is much less of problem than it used to be.
All images have noise. Usually noise is not welcome, specially if occurs in fixed patterns such stripes or bands. Noise increase as the ISO gets higher. The question if it interferes or detracts form the image quality or if it is artistically acceptable. Noise increase size of the compressed file and changes the purity of the colors and reduces the smootheness of tonal changes. There is luminance noise and color noise.
Noise can be reduce with software but bear in mind, the more you reduce noise, the more you loose in sharpness. On the other hand, if you need to sharpen the image the noise will increase. Good advise is to get images at the lower ISO possible or get a compromise in reduction when post processing.
For prints noise generally goes inadvertedly with modern cameras. For stockphotography you have to be extremelly careful because images are evaluated at 100%