Filters have long been a popular accessory for photographers and offer a number of different functions or effects. In both analogue and digital photography it is possible to recreate some of these in the darkroom or digital darkroom. However there has always been a benefit to getting it right in camera.

In black & white photography, colour filters in particular are useful as they can control how the colours in a scene are reproduced as greys. Normal black & white films are sensitive to all wavelengths of visible light although how they interpret the colours of that scene will not always match the way you see it. Colour filters therefore allow us to modify, at the point of capture, the way the film will respond to the different colours.

Each coloured filter produces a different effect on the scene.