LAB monochrome

there are lots of ways to convert to black and white in Photoshop, but one that you might not have heard of is the lab method. It won’t work on every image, but it can give impressive results in seconds. First go to Image>mode>lab Color. next bring up the Channels panel (Window>channels) then click on the lightness Channel. this removes all the colour information. often a contrast boost is necessary, so hit Cmd/ctrl+m for Curves and plot an S-shaped curve line. Finally, go to Image> Mode>grayscale.