10. Color Correction and Enhancement
The primary purpose of Photoshop is to act as a digital darkroom, where images can be corrected, enhanced, and refined. How do you know an image needs touch-up? You can pretty much assume every image can look a little (or even a lot) better than how the camera captured it. Whether it's adjusting the exposure, increasing contrast, or boosting saturation, Photoshop is the place to improve an image.
The image on the top is unretouched. The image on the bottom has been refined with three adjustment layers: one to enhance levels and two to adjust hue and saturation of the sky and vegetation.
Learning how to spot problems, and then matching the right correction technique, is an essential part of mastering Photoshop. There are several different tools available, some more useful than others. By analyzing the most important tools and which situations they might help you in, a more thorough understanding of color correction is possible.