An interesting side note on polarizing filters. They'll cut glare from water and glass, but not from bare metal or painted metal. I think it has to do with the amount and/or degree of polarized light that's reflected. Water and glass allow a certain amount of light to penetrate and not reflect. Metal and paint, while they absorb some of the light don't have the same absorption properties.
Consider a mirror. Without its silvered backing, it's just a piece of glass...and it WILL reflect some light but most of it passes through. Add the backing to it and almost all the light is reflected and we see it as a mirror image.
I've never tried a polarizing filter on a mirror, but I bet that it would have the same results as, say, a polished stainless steel Cobra.
r Sent from my Dreadnought using that barely tolerable Thunderbird email program On 7/16/2010 6:25 PM, humminboid@xxxxxxxxxxx wrote:
Hey, people; ------------------------------------------------------------------------I know some of you don't like good ol' Ken Rockwell. And he does create some controversy, but...he does have his moments. In one of his last postings, he suggests checking our filters for sharpness by looking through them, using a spotting scope or binoculars. Hmmm...why didn't I think of that?Well,I had nothing to do this afternoon, so I took my filters and binocs to the patio to see what I could see. Not a scientific test, but probably a good indicator.Amazing! None of my UV or Skylight 1A filters, or my ND 2 showed any softening of the image, but when I got to the circular polarizer; Whoa! Fuzzy image; I'll say! No WONDER I( couldn't buy a sharp image when I had it on at MMP.I guess when you stick four glass surfaces and a couple layers of polarizing film in front of a lens, something's got to give, especially among the "better,cheaper" filters.I have not had much practical use from my CPL, and the quality ones are so expen$ive, I may not replace it.One good thing happened, tho...I found out my Nikon 70-300 VR can use my 62mm Nikon 6T close-up lens by mounting it in a cheap 67mm-62mm step-down ring. The diameters are close enough so that there is no vignetting, and the close ups are very adequate. So, I don't have to buy the Canon 500D close up fliter at nearly $150. I do need more practice with it, tho.__________________ That old Black Nikon has me in its spell, That old Black Nikon that shoots so well...(To the tune of "That old Black Magic", with apologies to Louis Prima and Keeley Smith , who performed the best rendition,IMHO)
