3 Must Have Filters that will make any Photographers Life Easier!
How To: Using a Circular Polarizer by Digital Photo Secrets
Representations of electromagnetic waves of different polarizations: Right circular polarization (upper/right); Linear polarization (middle); and Left circular polarization (lower/left). Yellow arrows are the electric field, green arrows are the magnetic field. | NASA's Scientific Visualization Studio
B+W 67mm Circular Polarizer MRC Filter This one has 5 stars - brass ring filter. Absolute Must have for photography - brings out the colors in outdoor portraits, and enhances all water and sky shots as well. This is the size and type that fits with my Tamron lens.