The non-rotating Tiffen 127mm Ultra Pol Linear Polarizer Filter helps to greatly reduce reflections and glare by filtering out light that has become polarized due to reflection from a non-metallic surface. This results in a noticeable increase in the saturation of skies and foliage, as well as clearer imagery when photographing in hazy conditions. A linear polarizer differs from a circular polarizer in that it does not supports use of a camera's autofocus or auto exposure functions; it is best suited for use with manual cameras, such as view cameras, that are not dependent on internal mechanisms to determine focus or metering settings.
There is a total filter factor of about 4, requiring an increase of 2 stops for normal exposure. This filter is constructed from Water White glass and made using ColorCore technology, a process that involves laminating the filter substrate between 2 pieces of optical glass, grinding flat to a tolerance of 1/10,000th of an inch, and then mounting to precision metal rings. The non-rotating design of this filter is best-suited for use with lens hoods, adapters, or other rings for rotational control over the polarizing substrate.