To reach the shorter wavelengths, I taped a second polarizing filter to the first. I was hoping the two filters would act like a single filter with more narrowly spaced lines of polarization. It appears that this did help bring out polarization differences in the blue, but not violet to ultraviolet.
Here are the results for your pleasure. As you'll see, I need to do some more measurements to see if my results from the 3rd are typical.
|The colors of the sky were brighter in the East-West direction from 12:30 to 4:30 PM and then brighter in the North-South direction from 5:00 to 8:00 PM. But unlike blue, their total intensity's did decrease after 3:30 PM.|
|The violet/ultraviolet wavelengths were an anomaly. The sky continued to get brighter in this portion of the spectrum until 6:30 PM. The clouds also had a smaller effect on the sky brightness in this region. Odd.|