Page 31 - Enhancing CAD Drawings with Photoshop

4386.book Page 14 Monday, November 15, 2004 3:27 PM

14 CHAPTER 1 THE BASICS

Figure 1.14
The Preferences
dialog box

Figure 1.15
Sampling the Red
channel

9. Close the Color Picker and double-click the Zoom tool in the toolbox to return to 100%
magnification.
10. Choose Edit Preferences Display & Cursors again to open the Preferences dialog box.
Now that you have seen how the data in the channels is actually grayscale, you can uncheck
Color Channels In Color in the Display group and click OK.

11. In the Channels palette, click the green channel. The image in the document window changes.
12. Click the blue channel. Once again the image’s tonality changes as you are now viewing only
the blue data that the digital camera’s blue sensor captured.
13. Finally, click the RGB channel to turn on all three color channels. Now you see the composite
color image in the document window.