Editing Raw files: Noise Reduction
Digital noise is the bane of any photographer's life. It's caused (mostly) by using high ISO settings while shooting in poor light. Ironically, high ISO in good lighting usually has negligible noise effects. Smaller sensor cameras are particularly prone to this horrible side effect. Sharpening can also increase the look of added graininess in the file, so we have to use a little Noise Reduction to keep the result looking clean and clear of noise.
There are two kinds of noise: Luminance and Color noise. Both are horrible to look at, 
but perhaps color noise is worse:
- Luminance noise is just a graininess in the image, seen especially in the darker, underexposed parts of a scene. The higher the ISO rating, the more it appears. Underexposure will also show noise far more than if shooting in daylight. The Luminance noise slider softens the texture of the picture. Too much, and the image might take on a slightly...
