Post office web site - 308 CHAPTER 20 IMAGE EDITING Figure 20-3.
308 CHAPTER 20 IMAGE EDITING Figure 20-3. Set the opacity of various layers by clicking and dragging the relevant slider in the Layers dialog box. Making Color Corrections The first step when editing most images is to correct the brightness, contrast, and color saturation. This helps overcome some of the deficiencies that are inherent in digital photographs or scanned-in images. To do this, right-click the image and select Layers . Colors. You ll find a variety of options to let you tweak the image, allowing you a lot of control over the process. For trivial brightness and contrast changes, selecting the Brightness/Contrast menu option will open a dialog box where clicking and dragging the sliders will alter the image. The changes you make will be previewed on the image itself, so you should be able to get things just right. Similarly, the Hue/Saturation option will let you alter the color balance and also the strength of the colors (the saturation) by clicking and dragging sliders. By selecting the color bar options at the top of the window, you can choose individual colors to boost. Clicking the Master button will let you once again alter all colors at the same time. The trouble with clicking and dragging sliders is that it relies on human intuition. This can easily be clouded by a badly calibrated monitor, which might be set too dark or too light. Because of this, The GIMP offers another handy option: Levels.