Polarizing filter (photography)

<p>A polarizing filter or polarising filter  is a filter that is often placed in front of a <a href="/facts/Camera_lens/TkL6sd1b">camera lens</a> in <a href="/facts/Photography/ezLPT43M">photography</a> in order to darken skies, manage <a href="/facts/Reflection_(physics)/BhcjDs79">reflections</a>, or suppress <a href="/facts/Glare_(vision)/AzWTpN9x">glare</a> from the surface of lakes or the sea. Since reflections (and sky-light) tend to be at least partially <a href="/facts/Linearly-polarized/y4nJQKS1">linearly-polarized</a>, a linear polarizer can be used to change the balance of the light in the photograph. The rotational orientation of the filter is adjusted for the preferred artistic effect.
</p><p>For modern cameras, a <a href="/facts/Circular_polarizer/kPDwyboP">circular polarizer</a> (CPL) is typically used, which has a linear polarizer that performs the artistic function just described, followed by a <a href="/facts/Quarter-wave_plate/r2f9rx2S">quarter-wave plate</a>, which further transforms the linearly polarized light into circularly-polarized light. The circular polarization avoids problems with <a href="/facts/Autofocus/1B0tQWg2">autofocus</a> and the <a href="/facts/Light-metering/FjU1T7ST">light-metering</a> sensors in some cameras, which otherwise may not function reliably with only a linear polarizer.
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Polarizing filter (photography) open-in-new

Polarizing filter (photography)