Better default values of Vignetting

Hi,

It would be nice if, after adding vignetting, a slight effect were visible by default instead of this extremely strong effect, as if you were looking through a hole. By default, there should be an effect that could be used for most renderings without it being too noticeable.

Here is an example of how strong the effect is when I render in Rhino and activate vignetting.

Best-
Micha