Color Management Policies
Once you select a preferred working space,
you control how Photoshop deals with working
space issues under the Color Management Policies
section of Color Settings. You have three
- Preserve Embedded Profiles, and
- Convert to Working RGB.
The policy options for RGB are shown in
Figure 4 below.
4: Color Management Policies
section of Color Settings dialog.
Remember, turning off color management policies
does not stop Photoshop from using your selected
working space to render the file for viewing.
What it does do is stop Photoshop from embedding
a profile in a new document created in Photoshop,
embedding a profile in an untagged document
opened in Photoshop, or stripping a profile
from a tagged document that has a different
working space than the one selected in Color
If you choose to have color management policies
on (and you generally should), then you have
the choice of having a default policy of
preserving embedded profiles (Preserve Embedded
Profiles) or converting conflicting profiles
to your selected working profile (Convert
to Working RGB). No matter which policy you
choose, you should check all of the options
that require Photoshop ask you about how
to handle missing or mismatched profiles.
If you do not have these options checked,
then Photoshop can change your file without
notification. If the profile conflict resolutions
are checked on, then you will always be given
the opportunity to choose how Photoshop handles
the conflict, potentially avoiding a nasty
Changing Working Space
Once you have a Photoshop image file, with
or without an embedded profile, you can control
embedded working spaces through the Assign
Profile and Convert to Profile commands found
on the Image/Mode menu.
You use the Assign Profile dialog, shown
below in Figure 5, to remove an embedded
color profile from a tagged image, assign
a profile to an untagged image, or reassign
a new profile to a previously tagged image.
5: Assign Profile dialog box.
You use the Convert to Profile dialog, shown
in Figure 6 below, to convert a tagged or
untagged document to a new profile. The Source
Space is the current working space (which
is Photoshop's working space for an untagged
file), and the Destination Space is the working
space you want the document converted to.
You will almost always want to use the Adobe
color management engine to do the conversion.
Intent allows you to select the rendering
intent that you wish to use for the conversion,
which briefly is the method used to translate
the file to the gamut of the destination
6: Convert to Profile dialog
The difference between Assign and Convert
lies in how they treat the image file. The
Assign Profile command does not change the
pixel values of the image when a new profile
is assigned; therefore, the image can look
quite different after assigning a new working
space. The Convert to Profile command does
change the pixel values of the image in an
attempt to preserve the appearance of the
image when assigning a new profile.
Finally, using the Save As command on the
File menu allows the removal of the embedded
profile by unchecking the ICC profile option
when saving a new copy of the image file.
Copyright 2002 Michael W. Rollins