The 52mm Drop-in Circular Polarizing Filter from Canon
is used with long Canon lenses that accept rear-mounted drop-in filters.
The filter is rotated from a ring on the outside of the filter mount.
You do not have to remove the filter to use it. The glass is secured
within a strong metal frame that slips in and out of the rear mount with
ease. The degree of polarization can be seen through the viewfinder of
your camera as you rotate the filter.
Light rays which are reflected become polarized. A Polarizing
filter is used to select which light rays enter your camera lens. It can
remove unwanted reflections from non-metallic surfaces such as water or
glass and also saturate colors providing better contrast. The effect
can be seen through the viewfinder and changed by rotating the filter.
The filter factor varies according to how the filter is rotated and its
orientation to the sun.
Along with a UV or Skylight Filter, a polarizing filter should be
a part of everyone's gear bag. It can turn a run-of-the-mill image into
a stunning, creative photo by increasing color saturation.
EF 200mm f/2L IS USM
EF 300mm f/2.8L IS USM
EF 300mm f/2.8L IS II USM
EF 400mm f/2.8L IS USM
EF 400mm f/4 DO IS USM
EF 500mm f/4L IS USM
EF 600mm f/4L IS USM
EF 800mm f/5.6L IS USM