I have a large image (all one layer) from which this example is cut:
I want to alter the image such that the white and off-white pixels are replaced with the blue color. I would think that the tool called the "Color Replacement Tool" would be used for such a thing, tools like it have done the job in other programs that I've used. I can't make it work for this, however. It seems to do all manner of sophisticated and bizzare stuff instead of a very basic color substitution.
In other programs that I've used one would select a color (white), a second color (blue), and a tolerance (call it 70%) and brush around and the white is replace with the blue (or vice versa).
Can someone explain how to acheive this behavior in CS5?
This is not remotely a Color Management issue, but a Photoshop-specific question.
Color Management is a term of art defined as the science of maintaining the colors from capture to print.
I suggest you post in the Photoshop forum for the platform of your choice, Macintosh or Windows.
By the way, I assume you're using Adobe Photoshop, as opposed to Adobe Illustrator. "CS5" encompasses several applications. Obviously you want to look for the forum applicable to your application.