Using Filters - For Photography and Photographers
If you"re travelling, the amount of space you can afford for accessories is small. But although filters are rarely essential, they are extremely portable, and can have a dramatic result on your pictures. Most filters are designed to fit on the end of the lens - either screwing directly into the thread of the lens itself (round filters) or slotting into an adaptor which screws onto the lens (square filters). Square filters have the advantage that they can be changed quickly, and can be used on several different-sized lenses. Some digital cameras offer a range of electronic effects, which mimic the function of a filter.A useful all-round filter is the skylight, which cuts out some of the UV glare found in coastal or mountainous areas whilst warming the colour of the shot slightly. A fitted skylight can be left on the lens to protect the front element from dirt and damage.
Filters can be divided into three broad groups. Colour correction filters are used with slide film, and alter the overall colour balance for different lighting types. Filters for black-and-white pictures are strongly coloured to increase contrast or change the tonal balance. Most other filters are designed to have a pictorial effect over the image.
Multi-image filters
These lens attachments create a kaleidoscopic image of the scene in front of you - multiplying the subject a number of times. Different filters provide different numbers of images. Of limited use, as results are repetitive.
Solid colour filters
Filters with uniform, bright colours are usually reserved for use with black-and-white pictures, altering the relative strengths of different tones, and providing dramatic cloudscapes. But they can occasionally be used with colour scenes.
Polarisers
A polariser is one of the most desirable filters to take with you as it has so many uses. It can reduce reflections from glass and water. It can boost the colour of painted and shiny surfaces. It can be used to beef up the colour of the sky. You alter the effect"s intensity by rotating the filter.
Soft-focus filters
Soft-focus filters are designed to give a dreamy, misty feeling to shots - helping to create romantic mood or a feeling of nostalgia.
Graduated filters
Graduates are particularly useful when faced with a large expanse of featureless sky adding colour to just one half of the scene. The strength of colour and steepness of graduation increases with wider lenses and smaller apertures. Natural-looking or neutral colours, such as blue and grey, are the most useful.
Warm-up filter
Warm filters add a yellow or orange tint to a picture. This takes away the blueness of a misty day or a mountain panorama. It can also be used to give portrait subjects a stronger suntan.
Starburst and diffractors
Starburst filters have an etched grid, which turns bright lights in a scene into stars.