tenia por ahi un hilo guardado acerca de esto. Copio y pego algunas de sus frases.
RAW is not always "RAW" and when it becomes RAW.
Nikon's RAW files are not super neutral copies of the recorded
raw sensor data, some of their settings affect the analog
processing engine before the data reaches the AD
converter...especially the white balance settings.
are you suggesting that white balance affects the raw image
at acqusition? I would be surprised by this.
No, Nikon explained it in detail in one of their PDFs with
charts and what else. There are clearly some tweaked parameters
in the analog processing pipeline *before* the image gets
digitized. I think they introduced this concept as the D300
came out.
Right AFAIK, it works like this: the amplifiers (which are analog
devices) affect the sensitivity of the sensor. The white balance
setting works by altering the ratio of red and blue channels.
Noise in these channels can be reduced by applying some of this change,
at time of image capture, before digitization, by changing the gain of
the amps for the red/blue channels.
Auto is a safe setting if you're a RAW user. Except maybe in scenes
where it detects as say, incandescent, but there are blue hot spots
which are in danger of blowing out, in this case it would be better if
you over-ride it as Daylight if thats what you really want.