Controlling the color of an image is the ability to change the contrast. This is used either to correct the tonality or to increase or decrease contrast for effect. Other adjustment in colors,
- Contrast. Aside from color, the ability to change photograph's contrast is one of the most important controls of this program. Photoshop offers several different methods.
- Levels. By far the most useful contrast and tonal control is Levels. Use it for changing the contrast and tonality of shadows, mid-tones, and highlights, not only on a four color photograph, but also to each of the re, green, and blue channels. This, in turn, can also control color balance.
- Adjusting contrast. Beneath the histogram are three sliders, representing shadows, mid-tones, and highlights. When adjusted separately, they will change the brightness of that part of the tonal range. Moved to the left, it becomes brighter between the three parts of the tonal range determines the contrast of the image. Though each image will require individual correction, it is a good idea to adjust the shadows and highlights first, to set the darkest and lightest part, and then adjust the mid-tones.
- Histogram. The histogram is a diagram of the level of tones a photograph contains-running from left to right:shadows, mid-tones, and highlights. A low-key image with a large amount of shadow tones would show a high amount of activity on the left of the histogram. A high-key image, which would be