Adjust Hue/Saturation/Brightness
Before proceeding with this topic you need know how to work with selections.
This feature works only with RGB/Alpha Channel image formats.
Adjust hue, saturation and brightness of a portion of image
1. Select a region with the selection tool. If no selection is active, the adjustments will apply to the whole image.
2. Choose Draw/Adjustments-Effects/Hue-Saturation-Brightness or press "U".
3. The dialog box Adjust Hue - Saturation - Brightness opens.
4. To get a better idea of the adjustments you're doing, we recommend you to activate the Preview option. It permits you to see the changes in background (editor and preview windows).
5. Specifies the Hue value you wish to add to the current image. The value you specify is added (or subtracted if this is a negative value) to the current image hue (tint). By changing this value, you shift all image colors (in the color spectrum). Valid values are in range -180 to +180.
6. Specifies the Saturation value you wish to add to the current image. The value you specify is added (or subtracted if this is a negative value) to the current image color saturation. Valid values are in range -100 (grey scale) to +100 (very coloured).
7. Specifies the Brightness value you wish to add to the current image. The value you specify is added (or subtracted if this is a negative value) to the current image brightness. Valid values are in range -100 (dark) to +100 (very light).
8. When done, click OK.