Display Brightness Issues
I can't adjust my brightness anymore. It stays at the same brightness regardless of what the brightness is set at. I thought it was just my keyboard but it won't work manually either. I have an older Mac (iMac 2009). So it doesn't have ambient light sensors, so it can't adjust brightness automatically. I haven't had this computer for long either, only been using it for 3 or 4 month. However, it has been upgraded to MacOs High Sierra, but this is a very recent issue. I do digital art on my computer, so brightness is a big issue for me. Right now it's stuck on a slight dimmer brightness. I don't know what to do.
iMac, macOS 10.13