Channel Mixer in Photoshop Elements 5 and above

The "Channel Mixer" command lets you adjust an image by re-mixing its color channels. To use it efficiently, bear in mind the three sets of complementary colors: "Cyan - Red", "Magenta - Green", and "Yellow - Blue".

1. In the Effects palette, double-click the "Channel Mixer" thumbnail.
2. In the dialog box, choose the proper color channel from the "Output Channel" menu. For example, to alter the blue-to-yellow ratio, you select the "Blue" channel.
3. Try to adjust color with the "Source Channels" sliders, keeping your eye on "Total" percentage. For example, to fix a blue cast, you reduce this value; to remove yellow, you push it over 100%.

In the meantime, the "Channel Mixer" is a great tool for Black & White conversions:

1. At the dialog bottom, check the "Monochrome" option. The image turns to grayscale.
2. Redistribute luminance with "Red", "Green", "Blue" sliders to achieve the best possible tone and detail (screenshot).

In Photoshop Elements, the "Channel Mixer" can edit only the current layer. To adjust a layered image as a whole:

1. In the Layers palette, select the front (uppermost) layer.
2. Press [Alt+Ctrl+Shift+E] to merge all visible layers to a new layer.
3. Edit the created layer with "Channel Mixer".
4. If you need a kind of "color spot" effect, add a mask using the "Add Layer Mask" command.

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