First validation with polarization

As can be seen on the left (photo), LCD screens like on this iPad 1 are fully linearly polarized.  The big black disk is a linear polarizer rotated 90 degrees from the screen.   My first attempt at a serious polarized rendering has some obvious problems!   Could be the polarization infrastructure is wrong.   Or the Fresnel Equations.   Or both :)    I'll start by trying Brewster's angle tests tomorrow.

Left: photo.   Right rendering.   Lots of problems!