When I retired and switched to a 27" IMAC, the screen was way to bright after dark with the room lights dimmed. This app works very well.

It is well supported by the developer...I sent him an email asking for a key combo for an activity I will do often, and within an hour he emailed me back asking if I wanted a link to the updated app.

Even with the standard version, I was quickly able to create and save some presets, using just the menus and not reading any 'how to,' with the normal amount of trial and error.

[About these stars: I was not able to change a rating, and it would not let me leave one blank! I HAVE NO IDEA AS TO STABILITY YET.