My screen (21.5-inch 4096 x 2304) on my iMac is losing its color defination. A rain bow is now a white arc, and the shadows are starting to grow and get darker.
My display is starting to wash out. sample, rainbows are now simply white arcs and shadows are starting to get darker and washing out details. Any help or thoughts?
iMac 21.5″ 4K, macOS 10.13