ADJUSTING IMAGE TONE & CONTRAST

The first thing you'll probably want to do to this photo is adjust the overall lightness and darkness using the Levels command.

From the Image menu, select Levels, or use the keyboard shortcut, Command L (Control L for Windows). The Levels dialog box will appear:

You can alter the contrast of the image by adjusting the Input Levels slider directly below the histogram. This slider is made up of three tiny triangles that you can move to the left or right. Moving to the left lightens; moving to the right darkens.

Each triangle lightens or darkens a particular tonal range:

Shadows (black triangle): Darkens or lightens only the darkest color tones (pixels) in the image.

Midtones (gray triangle): Darkens or lightens all but the lightest and darkest color tones (pixels) in the image — the medium, neutral colors. This value is almost always referred to as the Gamma.

Highlights (white triangle): Darkens or lightens only the lightest color tones (pixels) in the image.

If the Preview Box is checked you can view changes on your image as you make them. You can also hit the Auto button and Photoshop will make the tonal adjustments it thinks are needed (and Photoshop is not always right so get into the habit of making these adjustments yourself).

You can get a good idea of what tonal adjustments to make by looking at the histogram, which shows how the shadow, midtone and highlight pixels are distributed in the image. An image with good tonal range has a balanced, even distribution of pixels in the histogram without gaping holes where there appear to be no pixels at all. The histogram for the image in this tip, for example, has a big gaping hole to the right of the peak in the highlights area. That means there are no pixels that are completely white (which is why the image is so dark). To correct this, move the Highlights triangle on the slider to the left until it is just at the base of the peak like in the animation below:

From here, you can adjust the shadows and midtones to your liking as well. Once you are done, click OK.

At anytime when you are working in the Levels dialog box, you can reset the tonal adjustments back to their original settings by holding down the Option key (Alt key for Windows), the Cancel button becomes a Reset button, click on Reset, and release the Option (Alt) key. Your settings will be back to the way they were when you first brought up the Levels dialog box.

Before Levels	After Levels