Black and White
Adobe PhotoshopCC provides a great way to convert a color image to grayscale with the Black & White feature. The great thing about the Black & White feature is that, like the Channel Mixer, you have a lot of control over how your colors are converted.
1- Choose Image→Adjustments→Black & White.
2- choose a Black & White preset from the Preset menu in the Properties panel.
3- In the Properties panel, manually adjust the conversion using the color sliders, apply an Auto conversion, or select a previously saved custom mix.
4- Preset menu: Select a predefined grayscale mix or a previously saved mix. To save a mix, choose Save Black & White Preset from the panel menu.
5- Auto: Sets a grayscale mix based on the color values of the images, maximizing the distribution of gray values. The Auto mix often produces excellent results, or can be used as the starting point for tweaking gray values using the color sliders.
6- Color sliders: Adjust the gray tones of specific colors in an image. Drag a slider left to darken or right to lighten the gray tones of an image’s original color.