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Message: <blockquote data-quote="WayneF" data-source="post: 108305" data-attributes="member: 12496">The camera does not report degrees K of correction.  It has another internal scheme for its color correction, somewhat proprietary, and Adobe and Nikon interpret the reported numbers a bit differently.   Adobe tries to convert to degrees K, but it is not particularly close.Do this to understand the issue:   (Other WB choices will show the same thing, but my example numbers are using Flash WB, and the point remains the same).    Set camera to Flash WB, which NIkon calls 5400K. Take a picture. Adobe will report it 5900K.Then set Flash WB in Adobe, and it will report 5500K (and the color probably improves, now that WB has been set).  If you are using Flash and RAW, then you should set Flash WB in Adobe, since someone has to set WB. Or, there are better methods too (the white or gray card).Don't go by the numeric values reported in Adobe.  They are sort of approximations, and don't matter. What matters is the image color being corrected.   Use a white card or a gray card, click it, and use whatever it says.  It will be right (if the card is neutral).All things change.  Light bulbs age and change color. Flashes change color with power level. Daylight changes with shade and sunset, etc.  All things change. WB is a moving target.   The neutral card is very huge help however, neutral remains neutral.If the gray card is 18%, then it is 18%. Whether it comes out that way depends on if the exposure does not make it brighter or darker.  It is not very absolute.  But if somehow the brightest part of the picture was of something 100%, and if it just reached the maximum level, then 18% would be near 18% (in linear RAW, at the sensor).But... the histogram is NOT linear data. It shows gamma encoded RGB data (sRGB is gamma 2.2 for example), so ideally and mathematically (if exposures are good), 18% comes out about 46% (at 117 on the 0..255 scale).  We don't see RAW, we only see gamma encoded numerical RGB values.   18% is 18% and is not supposed to be "middle", and FWIW, RAW 127 moved up to around 187 anyway (around 73% - EXCEPT, all the camera manipulations, WB, contrast, saturation, etc, etc, moves this around, this 73% is NOT a precise concept.  (still assuming gamma 2.2):You can see this if by trial and error, you take a picture with exposure adjusted to move the histogram data right up to the 255 border.Then reduce exposure exactly one stop.One stop is 50%, and we would expect right edge to drop to 127 in RAW linear data, but we never see RAW, or linear.In the gamma histogram, we see one stop drop back to around 73% (but with wide margin due to all the automatic adjustments the camera is doing).  It is far from center however.An 18% card is 18%, but it is gamma encoded in digital, which coincidentally brings it close to middle. It is NOT for the reasons we see told about it.  It is because all our RGB data is gamma encoded.</blockquote>

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