The G Vignette… that comes wih Gimp is ideal.
You get more controls (X, Y and so on), except for the artifact or light lines that come from all four corners.
The artifacts look bad on blue skies. They can be tamed by setting a bigger radius. The artifacts are more noticeable when using a smaller radius.
Too bad that’s the way it works if you use a smaller radius, it should not work that way.
I will use it only with a big radius.
Thanks all for taking a look!