Custom white balance with a Robin Myers Digital Gray Card
Ambient light plus one tungsten ceiling light behind the camera. The glare is caused by sun reflecting off snow outside the window. There was no direct sun in the room.

"100%" crops (Cropped, but not resized at all.)
300D Digital Rebel, sharpness 0, saturation 0, contrast 0
On a tripod, mirror lockup, remote release.
Two attempts at each aperture, chose the sharpest of the two
Put in manual focus, then to infinity, then back to AF at each aperture change