Photoshop

Mix color channels

Using the Channel Mixer dialog box, you can create high-quality grayscale, sepia tone, or other tinted images. You can also make creative color adjustments to an image. To create high-quality grayscale images, choose the percentage for each color channel in the Channel Mixer dialog box. To convert a color image to grayscale and add tinting to the image, use the Black & White command (see Convert a color image to black and white).

The Channel Mixer dialog box options modify a targeted (output) color channel using a mix of the existing (source) color channels in the image. Color channels are grayscale images representing the tonal values of the color components in an image (RGB or CMYK). When you use the Channel Mixer command, you are adding or subtracting grayscale data from a source channel to the targeted channel. You are not adding or subtracting colors to a specific color component as you do with the Selective Color command.

Channel Mixer presets are available from the Preset menu in the Channel Mixer dialog box. Use the default Channel Mixer presets to create, save, and load custom presets.

Mix color channels

In the Channels palette, select the composite color channel.
To open the Channel Mixer dialog box, do one of the following:
- Choose Image > Adjustments > Channel Mixer.
- Choose Layer > New Adjustment Layer > Channel Mixer. Click OK in the New Layer dialog box.
For Output Channel, choose the channel in which to blend one or more existing channels.
Choosing an output channel sets the source slider for that channel to 100% and all other channels to 0%. For example, choosing Red as the output channel sets the Source Channels sliders to 100% for Red, and to 0% for Green and Blue (in an RGB image).
To decrease the channel’s contribution to the output channel, drag a source channel slider to the left. To increase the channel’s contribution, drag a source channel slider to the right or enter a value between ‑200% and +200% in the text box. Using a negative value inverts the source channel before adding it to the output channel.
Photoshop displays the total value of the source channels in the Total field. If the combined channel values are above 100%, Photoshop displays a warning icon next to the total.
Drag the slider or enter a value for the Constant option.
This option adjusts the grayscale value of the output channel. Negative values add more black, and positive values add more white. A ‑200% value makes the output channel completely black, and a +200% value makes the output channel completely white.

You can save Channel Mixer dialog box settings for reuse on other images. See Save and reapply adjustment dialog box settings.

Create monochrome images from RGB or CMYK images

In the Channels palette, select the composite color channel.
To open the Channel Mixer dialog box, do one of the following:
- Choose Image > Adjustments > Channel Mixer.
- Choose Layer > New Adjustment Layer > Channel Mixer. Click OK in the New Layer dialog box.
Do one of the following:
- To set Gray as the output channel, select Monochrome. Monochrome creates a color image that contains only gray values.
- To create a grayscale, apply a preset channel mix. Photoshop provides six default Channel Mixer presets for RGB images:
  Black & White Infrared (RGB)
  
  Red=‑70%, Green=200%, Blue=‑30%
  Black & White With Blue Filter (RGB)
  
  Red=0%, Green=0%, Blue=100%
  Black & White With Green Filter (RGB)
  
  Red=0%, Green=100%, Blue=0%
  Black & White With Orange Filter (RGB)
  
  Red=50%, Green=50%, Blue=0%
  Black & White With Red Filter (RGB)
  
  Red=100%, Green=0%, Blue=0%
  Black & White With Yellow Filter (RGB)
  
  Red=34%, Green=66%, Blue=0%
To control the amount of detail and contrast in the images before you convert them to grayscale, use the Source Channels sliders.
Before adjusting the percentages of the source channels, view how each source channel affects the monochrome image. For example, in RGB, view the image with the Red channel set to +100% and the Green and Blue source channels set to 0%. Then, view the image with the Green source channel set to +100% and the other two channels set to 0%. Finally, view the image with Blue source channel set to +100% and the other channels set to 0%. For best results, try adjusting the percentages of the source channels so the combined values equal 100%.

Photoshop displays the total value of the source channels in the Total field. If the combined channel values are above 100%, Photoshop displays a warning icon next to the total.
(Optional) If you select and then deselect the Monochrome option, you can modify the blend of each channel separately, creating a hand-tinted appearance.
Hand-tinted effect created by selecting (left) and deselecting (right) the Monochrome option
(Optional) Drag the slider or enter a value for the Constant option.
This option adjusts the grayscale value of the output channel. Negative values add more black, and positive values add more white. A ‑200% value makes the output channel completely black; a +200% value makes the output channel completely white.