11 Ways to Desaturate in PhotoShop

There is an old saying that PhotoShop always has three ways to do a given task. Three only? That sounds like a low estimate. I’m currently working on a programming project where I’d like to replicate some results from PhotoShop, so I started with simple task – desaturating an image – converting color photo as black & white.

In the following examples, I’m using color test pattern from GPUImage. It contains 64^3 pixels, organized in a grid. It is originally designed for color lookup, but as it visualizes the differences quite nicely, I decided to use it here. Here’s the original pattern looks like this:


Next, the B&W conversions. Pay attention to hue changes and smoothness of the gradient.

  1. First, the obvious Image -> Desaturate. Same effect can also be achieved with Hue/Saturation adjustment layer.
  2. Vibrance/Saturation adjustment produces different look.
    Vibrance/Saturation Adjustment
  3. Black & White adjustment with default settings.
    Black & White Adjustment
  4. Converting to HSL and taking Lightness channel only. This almost same as Desaturate, but it appears slightly lighter.

    Convert to HSL, Lightness channel

  5. Converting to LAB and taking Lightness channel only.

    Convert to LAB, Lighness channel

  6. Image -> Mode -> Grayscale. Very close to LAB, but again there is difference in contrast.


  7. Camera RAW: HSL Saturation -100
    ACR HSL Saturate -100
  8. Camera RAW: Saturation -100
    ACR Saturation -100
  9. Camera RAW: HSL Grayscale mode with sliders at zero. Note the crude changes in intensity when hue changes.

    ACR Gray Mixer

  10. Gradient Map
    Gradient Map
  11. Channel Mixer all values at 33%
    Channel Mixer 33%

If you know any additional ways that produce different results, please leave a comment!