Heliopan 55mm Circular Polarizer Filter with Schott Glass

Circular Polarizer Filter is not something you want to leave on your lenses at all times though since it reduces light transmission and it can potentially make the sky look unevenly gradient when using wide-angle lenses.
A circular polarizer is designed to do one thing: remove or control reflections from surfaces like water, glass, paint, leaves, sky, buildings, streets, and the list goes on. When light hits those surfaces they create glare that increases highlights, reduces color and detail.

Using a polarizer in landscape photography is often advised. And with reason: colors will be enhanced, reflections in water and on the leaves can be removed, and skies can turn deep blue. But it is not advisable to use a polarizer as a standard filter, because there are situations when it can turn against you.

A Circular Polarizer is used on cameras with beam splitting metering systems commonly found on auto focus SLR’s (for most 35mm auto-focus cameras see your camera manual). The Standard Circular Polarizer filter blocks 1.5 stops of light and is one of those must have filters.

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