I had the recent experience of noticing that one of my external Samsung monitors was very dim compared to the other one. One was very bright and the other dark. Same settings in push button menu on the monitor? What the hell!
What type of monitor?
I am using two Samsung LU28R55 24″ monitors as externals to my iMac. However, if you are experiencing the same issue I am, this easy fix will probably work for you, even if you are using different models of Samsung external monitors.
Settings on monitors and on Mac.
The bright Samsung monitor setting was set to SAMSUNG MAGIC Bright and set to Cinema which produced a wonderfully bright, even balanced display. My second monitor was dark and dim and the SAMSUNG MAGIC bright option was greyed out? So I couldn’t understand why one had that option and other didnt.
Look into System Preferences > Displays.
Click on the dim monitor and look for this toggle, High Dynamic Rage. If it’s toggled, UN-TOGGLE it and Shazam….your SAMSUNG MAGIC Bright setting should be accessible and you can set your monitor to the Cinema option.