Clear days tend to create a lot of atmospheric reflection (haze) and the polarizer is especially effective at minimizing this.  Whereas the sky in bottom image is washed out, the sky in the top image has much richer colours and more detail.  The polarizer renders the sky darker while having a minimal effect on other parts of the scene; this allows you to open the lens aperture further, giving better exposure values and greater detail to other parts of the image (e.g. the city portion of the top image). For a very bright sky use  in conjunction with a Graduated Neutral Density filter for best results.

        The polarizer filter reduces light entering the lens that is oriented in a single plane (polarized light) without affecting colour temperature.  Light reflected off glass or water, as well as some of the light emitted from the sky on a clear day, is polarized.  When rotated to the appropriate angle, the polarizer can largely eliminate reflections off glass or water.  Furthermore, the polarizer will reduce glare and excess sky light, thereby increasing sharpness, contrast and colour saturation of the image.

        The circular polarizer filter produces the same effect as the linear polarizer but (due to the light being circularly polarized before it enters the lens) does not cause interference with the lens' auto sensors. If using the auto sensor functions on a lens, this filter type is recommended.  

• 3 x 3"

• 3 x 4"

• 4 x 4"

• 4 x 5.65"

• 5 x 5"

• 5.65 x 5.65"

• 6 x 6"

• 6.6 x 6.6"