How and in what kind of situations should it be used? For myself
the easiest way to understand UniWB was the following. Most
current digital cameras have twice as much green light sensors
as they have reds and blues (referenced as RGBG). Now to achieve
neutral gray by changing white balance, usually the red and blue
channels need to be amplified more than green. Just a few
examples (for Canon 350D): So when your camera generates JPG
based histogram (where your in-camera white balance setting is
taken into account regardless the fact you shoot RAW) under
tungsten lightning, the blue channel will be shown as clipped
far before it actually is. Same goes for red channel using Shade
WB. UniWB's main idea is to set all WB multiplier's to 1, so
your histogram is as close to reality as possible and you can
achieve optimal exposure. To use UniWB, simply find a RAW file
for your camera, download, copy to your memory card and set the
camera's white balance using that photo (most of the modern
cameras can set WB based on