The "Channel Mixer" is also a great tool for Black & White conversions:
- In case of multi-layered image, select the uppermost layer and "stamp" all visible layers by pressing [Alt+Ctrl+Shift+E] keys.
- Open the "Color and Tone" dialog and apply the "Channel Mixer" command.
- At the bottom of the dialog box that appears, check the "Monochrome" option. The image turns to grayscale.
- Redistribute luminance with "Red", "Green", "Blue" sliders to achieve the best possible tone and detail (screenshot).
- If you need a kind of "color spot" effect, add a mask using the "Add Layer Mask" command.
