Curves adjustment

Adjust the colour, tone and alpha channels with the curves adjustment, either on individual channels or by adjusting the master curve.

Before and after adjustment applied.

You can use the Curves adjustment to manipulate individual colour channels. The adjustment can be used on placed images as well.

Apply this adjustment via the Adjustments panel using the following settings:

Colour space—select a colour mode (Grey/RGB/CMYK/LAB) from the first pop-up menu.
Channels—specify a single colour channel to apply the adjustment to, including the layer's alpha channel. Master (the default choice) applies the adjustment to all colour channels*, excluding alpha channel*. Select from the second pop-up menu.
Spline—displays the curves spline chart which can be shaped to adjust the design's tonal range.

To adjust a curves graph:

On the curves graph, do any of the following: