The Tiffen 4 x 4" 85B Linear Polarising Filter combines an 85B colour conversion filter with a linear polarising filter to merge the effects of both types of filters into a single convenient solution.

The 85B colour conversion aspect of the filter provides a warming effect and decreases the colour temperature from 5500K to 3200K, allowing the use of tungsten-balanced films in daylight conditions.

The linear polarising aspect of the filter helps reduce reflections and glare by filtering out light that has been polarised due to reflection from a non-metallic surface. This results in a noticeable increase in the saturation of skies and foliage, as well as sharper images when shooting in hazy conditions. A linear polariser differs from a circular polariser in that it does not support the use of a camera's autofocus or automatic exposure functions; it is best suited for use with manual cameras, such as view cameras, which do not rely on internal mechanisms to determine focus or metering settings.

There is a total filter factor of approximately 6x, requiring an increase of 2.6 stops for normal exposure. Tiffen filters are manufactured using ColorCore technology, a process that involves laminating the filter substrate between 2 pieces of optical glass and grinding it flat to a tolerance of 1/10,000th of an inch. This filter measures 4 x 4" / 101.6 x 101.6 mm.


Features:

- Combination of linear polarising and 85B amber colour conversion filter.
- Total filter factor of approximately 6x requires 2.6 stops of additional exposure for normal results.
- The warming 85B colour conversion filter decreases the colour temperature from 5500K to 3200K for the use of tungsten-balanced films in daylight conditions.
- The polariser helps reduce reflections and glare by filtering out light that has been polarised due to reflection from a non-metallic surface.
- Eliminates haze in distant landscapes and provides more saturated and vibrant colours.
- Strongest polarising effect when used at a 90° angle to the sun.


Specifications:

- Type: Combination of amber colour conversion and linear polariser
- Size: 4 x 4" / 101.6 x 101.6 mm
- Grade: 85B
- Filter Factor: Approximately 6 (2.6 stops)
- Effect: The polariser eliminates reflections and haze and enhances colour and tone saturation. The 85B decreases colour temperature
- Colour Temperature: 85B: 5500K to 3200K
- Construction: ColorCore glass