When I remembered that a polarizer filter had the same effect of reducing the amount of light passing through the lens as an ND filter, I had an idea. I always have polarized sunglasses in the car, as they help a lot when driving in bright sunlight, especially after the rain. (via Useful Photography Tip #39: Use Your Sunglasses As an Improvised ND/Polarizer-Filter)

When I remembered that a polarizer filter had the same effect of reducing the amount of light passing through the lens as an ND filter, I had an idea. I always have polarized sunglasses in the car, as they help a lot when driving in bright sunlight, especially after the rain. (via Useful Photography Tip #39: Use Your Sunglasses As an Improvised ND/Polarizer-Filter)

Source: thephoblographer.com