# Channel Mixer
The Channel mixer lets you create gray scale, sepia, or images with a color tint. With this tool, you have control of the red, green and blue channels individually, so you have great control when making color adjustments.
The Channel Mixer tool.
**Output Channel**\
The Output Channel is modified based on a mixture of the Input Channels. When you choose an output channel, it's value will be set to 100%, while the other channels will be set to 0%. The exception is when you select Gray. In this case, the red, green and blue channels will be set to 21, 72 and 7 to give a basic, balanced gray scale image.
**Input Channels**\
Using these sliders, you can increase or decrease that color's contribution to the output channel. If the Preserve luminance option is not checked, the total of the combined channels is calculated. If the value is not 100%, the image will be either darker or lighter than the original.
**Constant**\
This adds a constant value to the output channel.
**Preserve luminance**\
When checked, the colors will be adjusted while preserving the intensities of the original image. In that case, the Total for the three input channels will always be 100%.This option is not available for the Gray output channel.
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