I figured it must be adjusting brightness using webcam as ambient light sensor (either the usb one i have on cinema display or the one that is on the laptop display (which again is in clamshell, so 'dark' would be appropriate if that's what it's doing) I did notice that if i'm persistent on my keyboard, i can not only get the brightness OSD to appear, but pressing the key fast enough, i can get two or three bars to appear before it adjusts itself away.įor me, I discovered the slider in system preferences DOES change the brightness, but it just dims itself again to the lowest brightness, and the slider (only) moves itself down to about 10% lower than wherever i drop it). 4 update, i've been having the issue with cinema display being at the lowest brightness after wake from sleep and my only recourse to be a reboot.Įnabling / disabling night shift had no effect and neither the sudo command nor force stop from activity monitor for corebrightnessd have any impact for me. I hate opening the laptop because i do run parallels and i can't find the right setting to use both retina display and cinema display without going blind or tearing out my eyeballs. Fresh boot - everything is great (really - i love this old display)Įvery morning i come in to the office, connect to the dock in clamshell mode having manually put the machine to sleep about 14 hours prior and wake it using mouse (bluetooth or USB makes no difference). I have the same issue- 10.14.4 on 2015 rMBP 15' with 30' Cinema HD 2560x1600 display connected via mini DisplayPort. Building a CustoMac Hackintosh: Buyer's Guide

Adjust brightness mac display