I am currently doing experiments with polarizing optics and reflection from metal surfaces. However it's not as simple as it sounds in textbooks, so I was wondering if anyone had experience in these type of experiments. There seems to be a fundamental problem with identifying the transmission axis of a polarizer. I've tried using a reflection from a surface at the Brewster angle but it's not that accurate, I've also used a method of reflecting from a metal. This gives answers to a high accuracy (mainly because it has curve fitting analysis), however isn't supported by simpler experiments (eg; calibrate 2 polarizers with this method and cross them). I'd currently feel comfortable saying that I know the axis to 0.5 degrees accuracy however in the literature much higher accuracy is quoted. Also the polarizers I'm using are quoted by the manufacturer to have an extinction ratio of <10,000. This doesn't seem to be what I get... Can anyone help with these problems?