Curves

The dialog for adjusting curves can be started by clicking on "Colors -> Curves" on the user menu.

A. Highlights

B. Colors

C. Shadows

D. Adjust a curve by adding points

E. Draw a curve with a pencil

F. Set a black point

G. Set a gray point

H. Set a white point

The dialogs for adjusting curves and for adjusting levels allow you to deal with the entire color range. Unlike the dialog for adjusting levels, which includes only three parameters (the level of white, the level of black, and gamma), the dialog for adjusting curves gives you the opportunity to set an arbitrary number of points within the entire color range of an image. You may also use the Curves dialog for precise adjustment of the channels. You can save the settings you used during your work or upload previous settings.

When the Curves dialog opens, the color range is shown as a diagonal line. The horizontal axis shows the value for pixels of an original image (Input Levels), while the vertical axis shows the new values (Output Levels).