In terms of technical questions I receive from other fellow photographers, the one about filters ranks at the very top. Years ago I focused an important part of my attention on the use of filters. This has led me to think about why filtering has become such an important issue in photography, and landscape photography in particular.
In the heyday of film photography, filters were mainly used to overcome technical limitations. Photographers using black and white negative film used filters in order to change the tonal relationships given by different colours when photographed in monochrome. A red filter, for instance, was used to darken skies and make clouds become more apparent. When colour contrast was inexistent, colour filters were the only way to adapt tone to create contrast, and with it, make apparent edges and shapes that enhance the composition.
With the arrival of slide film in colour, another limitation arrived: dynamic range. Slide film, with its vibrant colours, has a weakness, and that is its very narrow dynamic range. Films like the venerated Velvia display a short...