b&w vs color in low light conditions

[STEVIEB]

In very low light situations, my inclination is to switch to bxw because the results are usually far better than color shots taken at the same ISO. Is there any technical reason this is true? Or is the amount of noise the same, but, to me, less objectionable in b&w?

[Norm in Fujino]

In very low light situations, my inclination is to switch to bxw because the results are usually far better than color shots taken at the same ISO. Is there any technical reason this is true? Or is the amount of noise the same, but, to me, less objectionable in b&w?

Most high-ISO noise is chroma (color) noise, not luminance, so if you switch to b/w, obviously it tends to look better--you've eliminated the chroma element. You can do much the same thing by lowering the saturation to about 3% in pp, and then trying various combinations of color temperature, hue and so on, to see what b/w effect looks best.

[Riley]

with black and white you can regain some speed with -1EV stop, without much difficulty, the deep darkness just seems to add interest

[mattdm]

Also, it gets hard for auto white balance to work in low light. Eliminate color, and presto, no one can tell that it's a problem.

Although I recommend still shooting in color and then using the Channel Mixer tool in a photo editing program to choose how to combine the three colors channels into black & white -- you can get really different effects by varying this.