Motorcycles

I've never quite minded the effect, but through the tinted visor on my Qualifier and my usual polarized shades all the tar snakes appear purple in the sunlight and sometimes freshly sealed asphalt turns green. That's kind of trippy.

It's even worse if the polarization of each is rotated.

The closer to 90° from one polarized lens to the next, the less light comes through. At 90° rotation lens-to-lens, all light is blocked.

Try it with your sunglasses and the visor removed from the helmet. Slowly rotate the visor and you should see it get darker and darker.