10 different ways to convert a color image to grayscale
There are many ways to convert a color image to grayscale in Photoshop. We'll review 10 of these approaches:
The following four approaches give you more control over the look of the final image.
1. Using Adobe Camera Raw
Go to Adobe Bridge; right click an image and select "Open in Camera Raw".
Click the "HSL / Grayscale" tab (the fourth from the left). Check the "Convert to Grayscale" box and move the various sliders to preference.
2. Using the "Black & White" adjustment layer
Select a layer in the layers panel and then click on "Black & White" in the Adjustments panel or click the adjustment layers button in the layers panel and select "Black&White". Move the sliders to preference.
If you wish to apply the conversion to the selected layer only (and not to all layers below) hold down Alt (PC) or Option (Mac), position the mouse pointer over the line that divides the image layer with the adjustment layer and click.
3. Using the Calculations command
Select Image > Calculations from the menu. Experiment with the various options and observe the changes to your image. When you are satisfied with the final result, click on "Result", select "New Document" and hit OK. You can then convert the new image's mode to Grayscale and RGB.
4. Using the Channel Mixer
Go to the layers panel and click the "Channel Mixer" adjustment layer. Check the "Monochrome" box and move the sliders to preference.
The following six approaches were common in the older Photoshop versions. Most of them are non-destructive yet they give you little or no control over the look of the final image.
5. Using a Black photofilter
Create a "Photo Filter" adjustment layer. Change the color to black and set the filter's density to 100%.
6. Using the Gradient Map adjustment layer.
Go to the layers panel and click on the "Gradient Map" adjustment layer.
7. Using a Solid Color adjustment layer
Go to the layers panel and click on the "Solid Color" adjustment layer. Select black or white as the layer color and hit OK. Change the adjusment layer's blending mode to "Color".
8. Using a Hue/Saturation adjustment layer
Go to the layers panel and click on the "Hue/Saturation" adjustment layer. Drag the Saturation slider to the far left. Avoid pressing Control-U (PC) or Command-U to decrease the saturation since this is a destructive approach to the particular tecnique.
Alternatively, you can add two "Hue/Saturation" adjustment layers. Then click on the first H/S layer and drag the Saturation slider to the far left. Click on the second H/S layer (below), change its blending mode to "Color" and drag the Hue, Saturation and Lightness sliders to preference.
9. Converting to LAB mode.
Select Image > Mode > Lab Color from the main menu. Go to the Channels panel and click the "Lightness" channel. Select Image > Mode> Grayscale from the main menu. Note that this is a destructive approach.
10. Converting to Grayscale
Select Image > Mode > Grayscale from the main menu. Note that this is a destructive approach.