1 The Director of Photography – an overview

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Camera filters
We use filters in cinematography to alter the image either for technical
reasons to correct the colour of the light to that required by the film
we are using, or because we may wish to change the image in some
way that will enhance our storytelling powers.The former is often necessary,
the latter much more fun.
The majority of coloured filters are known by numbers or a combination
of numbers and letters – for instance, 85 and 85B. These are simply
the catalogue number they are to be found under in the Eastman
Kodak Wratten Filter Catalogue. All filter manufacturers will use the
Wratten filter numbers for their version of the filter in their list that
conforms to the transmission characteristics of the filter in the Wratten
list.A Wratten catalogue complete with transmission graphs can be an
illuminating read once you know how to interpret the information.
Effects filters are usually described by some term that indicates
what change they will make to the image – for example, fog filter.
Colour-compensating filters
Colour-compensating filters, or CC filters, are carefully stepped filters in
the primary colours or their reciprocal colour. They are used, in front
of the lens, to correct the source light to the film in use. They come in
small steps so you need a lot of them to be able to cope with any situation.
In reality, we rarely use CC filters in cinematography – they are
mainly used in still photography to obtain an accurate original transparency,
as with the reversal process there can be no correction later.
Colour-correction filters
This phrase usually refers to filters used to correct a daylight scene
when shooting with tungsten-balanced film. The usual full correction
filter is the Wratten 85. The various alternatives are:
Wratten 85 Full correction
85B Full correction � slight warming – often used as
standard correction when filming for telecine, as
this can enhance the transfer to tape