by Julieanne Kost
There are times when you will want to use Image > Adjustments > Curves to modify an image instead of using an adjustment layer. This is true, for example, when adjusting a mask. The following shortcuts are handy when navigating the Curves modal dialog box. Note: these shortcuts are not always the same when using the Adjustments Panel to modify a curves adjustment layer.
Command (Mac) / Control (Win) + M displays the Curve Dialog Box
Command Option (Mac) / Control Alt (Win) + M displays the Curves dialog with the last used settings
With the on-image adjustment button (also known as the targeted adjustment tool or scrubby slider) off:
Command (Mac) / Control (Win) -click the image to add a point to the active curve only.
Command (Mac) / Control (Win) +Shift to add a point to all of the channels.
Shift -click in the image area to add Color Sampler point.
Option (Mac)/ Alt (Win) + Shift -click on a color Sampler point to delete it.
Click -drag on image to display a small dot on the curve corresponding to the value clicked upon.
Control (Mac) + tab and Tab (Win) will toggle focus from one point on the curve to another (as will the + and – keys).
Shift click to select multiple points on the curve.
Command (Mac) / Control (Win) + Delete to delete a point.
Use the arrow keys to move the select point one increment. Add the Shift key to move in greater increments (10).
Option (Mac)/ Alt (Win) + drag the black/white point sliders to display shadow/highlight that will be clipped to pure black/white.
Option (Mac)/ Alt (Win) + click the grid to toggle size.
Option (Mac)/ Alt (Win) + P toggles Preview on and off.