well i'm getting my screen next week (hopefully). If anyone wants I can whip up a little program that'll dim the screen (if its osd) according to time. so its super bright during the day, start to dim when sun starts going down every hour.
Well this is just a theory, have to get my screen before I can test this out.:D
The other, more electrical engineering method, is to get a photoresister and build a circuit to sense how much light is in the cabin and adjust the screen accordingly.
Software is the cheapest solution :D
The OSD is implemented in the LCD controller / firmware. How are you going to control that from software on the PC?
Generally, the OSD is a seperate piece of the puzzle. There are some controllers with it built in and, actually, I've seen inverters with POTS (potentiometer) for dual brightness settings. Check out your controller instructions for details. ZipLock, which controller and panel are you using?
I would bet money you can find someone out there who can or maybe you can program a program that when it is a certain time it sets the brightness and contrast to certain settings. If you really wanted to I bet you could do it by date also since winter has shorter days and the such