manual screen brightness control on a 21.5 2012 iMac running Catalina 10.15.7
Can anyone tell me how to adjust the screen brightness on a 21.5 2012 iMac running Catalina 10.15.7
iMac 21.5″, macOS 10.15
Hi Malcolm,
the F1 & F2 keys were not responding on my keyboard. The screen brightness adjustment slider was not present in the display dialog box.
I contacted Apple support and spoke to a consultant who suggested that I disconnect all my peripherals and power for a minute and then restart holding down the Option + Command + R + P keys.
When the iMac started up all was well. The F1 & F2 keys were responding and the brightness slider reappeared in the display dialog box.
An added bonus was that my Mac is running faster.
Thanks for your help.
