[Tig] Why Whites May Not Match note posted to TIG Wiki.
richard at filmlight.ltd.uk
Thu Feb 2 10:08:14 GMT 2012
Jim Houston <jdhouston at earthlink.net> wrote...
> On Jan 29, 2012, at 5:58 PM, Rob Lingelbach wrote:
>> "D65 white has a spectral definition: it was based on the spectrum of noonday sun at Rochester."
> Sometimes stories develop that come through the same route as Urban Legends...
> something we somehow would like to believe is true, but is not really.
> An accurate description of where all of the "D" colors come from can be found
> on page 7 of Wyszecki and Stiles (1982), the bible for early color research.
This is one of the many corners I cut in the argument to try and keep it
I had a look in my copy of Wyszeki & Stiles. It was sort-of based on
Rochester (and a lot of other places too). My basic argument was that we
actually compare our monitor whites to a true D65 spectrum, and if we
might not match; and this becomes a bit easier to grasp if we can talk
of a D65
light as a real thing.
In case anyone is puzzled by this...
If you have a D65 light, it has probably been balanced to give the same XYZ
as D65. If you have got a good one it will probably approximate to the D65
spectrum. However, a real lamp will never quite fit the D65 spectrum, which
is a very wiggly line.
If I have time, I might add this to the Wiki later.
PS: You know your are a colorist when you can spell 'Wyszeki' without
PPS: Crow tastes ok. You need lots of ketchup, though.
More information about the Tig