Curves Adjustment in Photoshop Elements 5 and above

"Curves" is the most powerful adjustment command in Photoshop. Although its functionality and work principles are very similar to those of "Levels", this method lets us edit virtually any tonal range, or even adjust several different ranges in different ways. Please note, though, that when unlocked in Photoshop Elements 6, this tool has 2 important restrictions - it only edits the current layer and the current color channel.

How to adjust image tone:

1. For a layered document, select the proper layer in the Layers palette.
2. In the Effects palette, double-click the "Curves" thumbnail. A dialog box will appear allowing you to adjust image tone by editing the graph. Generally speaking, the sharper your graph is the more contrasting the image will be.
3. Very carefully pull some middle point of the graph to brighten or darken the image midtones.
4. Pull the graph at some lower point rightward to decrease brightness in the darker areas (let's say, in "mid-shadows").
5. Uplift the upper segment to brighten the "mid-highlights" (screenshot).
6. To define tonal range more precisely, [Ctrl]-click a specific spot on the image. Then pull the graph at the added point to adjust the selected range.

Although in Photoshop Elements this dialog is missing the "Channel" menu, you can use it for color adjustments as follows:

1. In the Effects palette, double-click a "color channel" thumbnail. For example, to reduce yellow color you click "Select Blue Channel". Now the selected channel is displayed as a grayscale image; the two other color channels disappear.
2. Double-click the "Show Hidden Channels" effect. Now all the color channels are visible and we can see the composite image. Note though, that only the "Blue" is selected at the moment, so all the tools and commands only affect this channel.
3. Any tonal adjustments in this state alter the blue-to-yellow ratio. That is lightening the channel increases amount of the primary color, darkening the channel adds complementary color. So, by darkening image in the "Curves" dialog, you decrease blue (increase yellow) color; by brightening it, you increase blue (see example) .
4. After editing color channel, double-click the "Select RGB Channel" command in the Effects palette. Now you can resume editing of the composite image.

Attention! This tutorial is for Photoshop Elements 5 and above. Version for earlier versions available here.