Data Sheet

LTERS Reference dataFILTER FACTORS

Filter Factors

Since photographic filters absorb light, exposure must be increased to

compensate for the effective light absorbed. The number by which the

exposure must be increased for a particular filter used with a particular

film is called the filter factor.

While these factors for basic applications are given below, as well as on the

filter instruction sheet, the factor will vary according to shooting conditions.

The precise filter factor is determined by considering the film type and

specific light source. Therefore, filter factors indicated are for your reference

only. The filter factor and exposure compensation required is as follows:

The Production Process Of Hoya Filters

Automatic V-blender

Continuous

annealing furnace

Direct pressing machine

High speed

polishing machine

Vacuum evaporator

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