Invert will make a color image look like a photo negative. Color balance is a useful color correction tool if your image has distorted colors, or if you want to change the colors, like we have done with the blue duck. Hue-Saturation is perhaps an even better tool for correcting color problems. It's also a great tool for changing colors. As you can see, our yellow truck has turned blue without any change in the other colors in the image.
Curves is another color control tool.
Levels is an excellent tool for enhancing 3-D effects by adding highlights or shadow. You can also use it the other way around and make the image flat, using less contrast when it comes to color, highlights and shadows. Desaturate takes away the color information, but you are still in RGB space. Desaturate is excellent when you want to accentuate a certain part of the image. If the surroundings are desaturated, the colored part will catch the viewer's focus.