Adjust the slider towards the right for a lighter image or towards the left for a darker image. The Gamma Correction field updates to show the current numeric value.

or

Enter the value in the Gamma Correction field. An acceptable value is in the range 0-2, with 1.00 representing no correction. Decreasing the value results in a darkening of the image while increasing the value results in a lighter image.

Click the Apply button to process the image with the value entered.

or

Click the Preview button to see the change without modifying the image in memory.