Working with Modal Controls in an Action
Modal controls are pauses in an action; which allow you to modify a command before proceeding with the action. Modal controls are available for every Photoshop command that utilizes a dialog box, or any command that requires the pressing of the Enter/Return key to process the effect. For example, you create an action that utilizes a Levels and Curves adjustment, and you want the option to control the Levels adjustment each time the action is run.

Work with Modal Controls
Open a document, and then select the Actions palette.
Click the expand triangle of the action you want to modify.
Click the second column from the left to activate the Modal Control button.
Click an existing modal control button to deactivate the control.
Click the Play button on the Actions palette to run the action.The action stops and lets you control the command.
Adjust the image using the Exposure dialog box.
Click OK to continue the action.[View full size image]