I've got to get me one of those hats...
Despite Bill's apparently reproachful glance this is a posed portrait. The color cast is due to having bounced the flash (Nikon SB-600) off the ceiling, with the resulting colors filtering through the hat. (An appropriate fill flash front and center would have offset the color cast.) This is a tough room to shoot on a good day as there are almost always four different light sources present: incandescent, fluorescent, halogen, and natural light streaming through the windows in front. Ordinarily I would have removed the color cast, but in this case I kind of like it as is... (Your tastes may of course vary.)