Just to be sure I rechecked all my settings and it turned out my monitor automatically picked up a different color space with an other level of brightness. By adjusting this setting, the default setting of 50 turned out to be spot on again. 🙂
I think gamers would really appreciate a slightly more advanced brightness setting, with an image to set it up properly, in stead of an empty white screen. In main menu go to: "settings" -> "video" -> "brightness", to find the setting I'm talking about.
Here is an example of a set-up pattern, in the attachment.
