I'm not sure. But then again, you're not going to use your Kindle with max brightness are you? It's just impossible.
I've cranked the brightness of my PW to the max (was very painful to see), I took pictures:
http://s17.postimg.org/gvluxsc8v/photo_1.jpg
http://s30.postimg.org/k2f0jb9a9/photo_2.jpg