Desaturation is a quick way to create black and white images. Desaturation uses the midpoint between the high and low RGB values as the gray value. It results in a black and white conversion with less contrast than other methods.
There may be times when you want to apply different conversion methods to different parts of the image. Here’s how.
UPDATE: This tutorial uses some obsolete methods such as the hue/saturation method. I created this example about ten years ago, before Photoshop CS3 introduced black and white filters. If I were to redo this today I would use different conversion methods. However this tutorial, along with Selective Color, is a good example of how to use color selection during black and white processing. – DK
Genbaku Dome, Hiroshima Japan
The Genbaku Dome, or Hiroshima Peace Memorial is part of the Hiroshima Peace Memorial Park. I took this photo on my trip to Japan in 2012. Hiroshima itself is a very ordinary city. However the history of the city and the museum made the visit a very moving experience.
I processed this photo in Lightroom. Lightroom is currently my favorite way to process black and white. It adds a slight brown tint which gets rid of the blue tint that most digital b&w photos have.
For this photo I pushed the cyan and blue towards black to create a dark sky, and really boosted the contrast. I think it works for this subject.