if any of the fixes listed do not fix your washed out display please look into the following. Universal Access - Monitor Contrast Adjustments in OSX Be aware that OSX introduces a feature in the “Universal Access” utility that can severely limit the performance of your monitor. To review this feature proceed as follows: Click on the Apple icon (top-left) then on “System Preferences”
Next, click on the “Universal Access” icon (bottom-right). Ensure that the “Seeing” tab is selected. Under “Display”, ensure that the “Enhance Contrast” slider is as far left as possible - this is the normal position. If the slider is positioned even a small fraction of an inch from the left, there will be a loss of shadow contrast that can hide subtle shadow details in your images.
Hours troubleshooting ColorSync profiles only to find I’d “enhanced” contrast at some point. Ugh.
10.4: Avoid a fast user switching color profile bug - Mac OS X Hints