Just shot a beach scene using an old Graflex 4x5 camera and a Fujinon 125mm lens. The sun was in perfect place for a polarizing filter and when I held the filter to the naked eye, aimed at the scene, and rotated it, I easily saw variations in the effect of the filter. In the ground glass of the camera, though, I could see no effect from rotating the filter (or almost no effect). Eventually, I just took the position of the filter held to my eye and put it on the camera in that position, hoping for the best. Am I just seeing things (or in this case not seeing things) or does the ground glass not show the polarizing effect?