MacBook Pro Video output broken

It's strange. When logged in as normal user my video output is broken. Colors are off and everything looks like overexposed photographs or an old 8-Bit display. When I take a screenshot the screenshot looks perfect on another computer. Also when logging in with VNC from my iPad the colors are correct. And strangely when logging in as my "Admin" user everything is ok! I tried to change color profiles, resolution, fixed file permissions and even restored my system from a time machine backup. It even shows this behavior when I connect an external display. I have no idea what to do. Any ideas?

Thanks!

I attached a "photograph" of Finder, just so you see how it looks like...

You're the man! Thank you! The slider was way off. No idea who changed that setting. Didn't even know it existed. Maybe it was a software as I enabled "Enable access for assistive devices".

Thanks again! Now my Mac is usable again... :-D