Adjusting Levels

What to Know: The tonal range of an image represents the amount of contrast, or detail, in the image and is determined by the image’s distribution of pixels, ranging from the darkest pixels (black) to the lightest pixels (white).

• Click the Image drop-down menu located in the top bar of the application.
• Hover over Adjustments and select Levels. The Levels controls and a histogram appear in the Adjustments panel.

What to Know: The histogram displays the range of dark and light values in the image. The left (black) triangle represents the shadows; the right (white) triangle represents the highlights; and the middle (gray) triangle represents the midtones, or gamma. Unless you’re aiming for a special effect, the ideal histogram has its black point at the beginning point at the beginning of the data and its white point at the end of the data, and the middle portion has fairly uniform peaks and valleys, representing adequate pixel data in the midtones.

• Drag the left (black) triangle toward the right to the point where the histogram indicates the darkest colors begin. As you drag the triangle, the first Input Levels value (beneath the histogram graph) changes, and so does the image itself.
• Drag the right (white) triangle toward the left to the point where the histogram indicates the lightest colors begin.
• If needed, drag the middle (gray) triangle slightly to the left or right, to either lighten or darken the midtones. This step may not be needed at all.
• Click OK to execute the changes to the image.