A custom grayscale or spot color profile can be created based on the specific dot correction or gamma characteristics of the output device. You can also load CMYK profiles into the "gray" workspace menu to generate custom grayscale profiles based on CMYK space. (See Storing and Loading Workspace Profiles.)
To create a grayscale or spot color profile based on custom dot corrections:
Print a printed proof containing the calibration bar.
Use a reflection densitometer to take a reading of one or more scales on the printout calibration bar.
Do one of the following:
In Windows and Mac OS 9.x, choose Edit > Color Settings and select Advanced Mode.
In Mac OS X, choose Photoshop > Color Settings and select Advanced Mode.
Under "Workspace", for "Gray" or "Spot Color", select "Customize Dot Correction".
In Name, enter the name of the custom profile.
Do one of the following:
Use the densitometer reading to calculate the desired adjustment and enter the percentage value in the text box.
For example, if a 30% dot is specified and the densitometer reading is 36%, the halftone dot correction is 6%. To compensate for this correction, enter 36% in the 30% text box.
Add the adjustment point in the dot correction curve by clicking on it and drag it to change its value. This value then appears in the corresponding text box.
Click the "OK" button.
Store custom configuration files.
To create a grayscale profile based on a custom gamma:
Do one of the following:
In Windows and Mac OS 9.x, choose Edit > Color Settings and select Advanced Mode.
In Mac OS X, choose Photoshop > Color Settings and select Advanced Mode.
Select Advanced.
Under Workspace, for Gray, select Custom Gamma.
In Name, enter the name of the custom profile.
Specify the desired gamma value and click OK.
Store custom configuration files.
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