What happens when light enters a polarizing filter

Camera filters alter the entry of light into the camera lens. The altered light changes the image captured. Polarized lens filters are used to reduce glare or to adjust color and contrast. Installed over the camera lens, a polarizing filter is useful for darkening a blue sky and can create additional contrast when used in conjunction with black-and-white image captures. Polarized filters are generally loose fitted to the lens allowing rotation of the lens for optimal visual effects

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