[Andy Dunn]

Hey Bob

that is interesting. I have never tried down the center of the window and always gone off the braket. My car is not here to test. I'll have to try some friends cars with that method shortly. Do you think that perhaps the center area of the window is at a greater angle than the bracket? It is curve outward at that point. Did you zero the protractor off the frame...I forgot to....and thinking about that, it would give an different reading if the cobra was higher in the back than the front and many are. There is rake against the frame and rake against earth. I never considered this until now.

I just thought of an error in my measuring of angle with the gif and jpg technique. This assumes that the camera is taking a perfectly level picture when this is simply not true. The camera holder is most likely off a few degrees to one side or another for a variety of factors.

Andy