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idea, but in reality, it was poorly implemented (see the sidebar, “EXIF
Data and the Lie about Your Color Space”). The bottom line is that if you
are satisfied with the color the camera produces when you tell it to
produce a fixed RGB color space, all you really need to do is set up Pho-
toshop to deal with the EXIF data and assign the profile correctly to the
data.
Sidebar
EXIF Data and the Lie about Your Color Space: For whatever reason, when a consortium
of Japanese camera manufacturers came up with a method of identifying the RGB color space
of their camera data using EXIF data, they did so in an obscure and confusing way. In 1999,
the Japanese digital camera industry implemented a “standard format” they called Design Rule
for Camera File Systems version 1.0, or DCF for short. In that specification, the EXIF data simply
specified whether the camera data was encoded into sRGB based on the matrix setting con-
figured on the camera. If a camera encoded the data to Adobe RGB (1998) or any other avail-
able color space besides sRGB, the EXIF tag was set to “none,” causing Photoshop to produce
a Missing Profile warning dialog if the color settings were configured to warn the user. This
caused all kinds of problems, to the degree that Adobe had to produce a plug-in for Photoshop
7 (and a setting in the general preferences for Photoshop CS as well as CS2) called Ignore EXIF
profile tag (see Fig. 5-4). This sets Photoshop to ignore the color space specified in the EXIF
data and the result is a Missing Profile warning dialog, which allows the user to pick the correct
profile to assign. In late 2003, DCF 2.0 was introduced and it does specify Adobe RGB (1998)
in the EXIF data. Not all new cameras necessarily support this, however. None of this has any
effect on RAW data although it still does apply when a camera is set to shoot RAW + JPEG files.
Fig. 5-4 The Ignore EXIF
profile tag option in
Photoshop CS general
preference can be set to
ignore any EXIF data
pertaining to the color
space in a digital camera
file.
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