Get rid of Dark Corners

By the reason of lens, The DC user sometime will find their photos have 'dark corners' when shot with wide angle.This function is designed to fix this problem.

Enter the function:

Select 'Get rid of Dark Corners ' from popup menu of 'Enhancement' button.

The interface and the description:

First of all, adjust the radius and position of the reference circle by drag and move the control point. Place the circle at the begining of shadow. The pixels inside the circle will not be processed.

Then, adjust the range parameter. The smaller range means faster gradient change. Find the best pair of 'range' and 'circle position' to create smooth output.

The first step is the key to success. Too small of radius will brings shadow inside the circle, while too large radius will cause obviously change from highlight to shadow outside the circle.