Fri Oct 19, 2012 11:50 am
Because of how digital sensors achieve different colour temperatures; applying positive and negative gain to the separate colour channels, the neutral white balance, or native colour temperature is the point at which there is 0 gain on any of the channels.
With Bayer pattern sensors, such as this camera, where green photosites represent 50% of the sensor, the native colour temperature or white balance would almost certainly have a green tint and not be any particular "temperature", so to speak.
Google "uni-wb" or "unified white balance" for a demonstration of how it would look.
So in effect, there would be no native colour temperature in the traditional sense, because the neutral point would not be calibrated for a specific conventional colour temperature.
So the optimum colour temperature of any bayer sensor would result in a green cast image. You can see this also if you convert the dng's to cineform raw and don't carry across the colour temperature meta data.
In any other temperature setting, gain is applied in various measures to each colour channel, which means practically speaking, if you want to film in standard situations, none of the colour temperature settings would be native, whether tungsten, daylight, fluorescent etc. It would be very useful if BMD added to a feature to the camera whereby we could see when an individual colour channel clips, this would help to better expose. Otherwise, allow us to have the neutral temperature selectable from the menu, so that we can see at what point the channels clip before any gain is applied.
Tom Majerski
Colourist at Tracks and Layers
http://www.Tracksandlayers.com
Motion Graphics - Colour Grading - VFX