Circular Polarizing Filters And Vignetting - Pentax smc -DA Operating Manual

Circular polarizing filters and vignetting

Circular polarizing filters are thicker than regular filters. Depending on the lens that is
mounted and the shooting conditions, vignetting may occur in the four corners of the image.
Refer to the "Compatibility table for PENTAX circular polarizing filters" on the following page
for information on compatibility of the PENTAX circular polarizing filters (currently not
available) with various lenses. There are two types of PENTAX circular polarizing filters.
The A type (on the left in the diagram below) and the B type (on the right in the diagram
below). The B type filter is thinner than the A type filter.
A type B type
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