Real D200 Color
Temperatures for White Balance
Prepared 2007-01-21 (149/77826) by Bill Claff
With the ability to compute Color Temperature from White
Balance values in NEF files (Real D200 Color
Temperatures for Choose Color Temp) I decided to test the various
Options shown on page 200 of the D200 Manual.
Swatches of the 42 images are attached and show the Color Temperature as
published as well as the value I computed.
The published values are on the left and the computed values on the right.
All of the Incandescent and Sunlight values were in close agreement.
All of the computed Flash values were significantly higher than the published
values.
The values were also slightly on the blue side of the Planckian Locus; not
surprising given the characteristics of flash.
The computed Fluorescent values were really all over the map compared to the
published values.
And some of these values were far of off the Planckian Locus; not surprising
given the nature of fluorescent light.
I hope to perfect a reasonable technique for computing "tint"
(distance off of the Planckian Locus) and post more exact results in the
future.
I did this out of curiosity, I never use this feature of the White Balance
Options; as I have found that Auto White Balance does an excellent job.
When I can compute "tint" reliably then I think an investigation of
Auto and White Balance Preset might be revealing.