So what are they? Filters are a small “cap” that are attached to the end of your lens which help enhance your image in different ways, depending on which you use.
Do I really need one?? Well yes and no, it all depends on what you plan to accomplish with your final image. You will find that you will more than likely need one sooner or later, especially when you start to realise the impact that they can have on your photography.
What types are there? This is impossible to answer as there are hundreds of different filters and variants! I will try to give you a guide to the most popular and what they are used for....
UV Filter: This filter is very popular with many photographers, whether armature or not. They are mainly used to help protect your lens from dirt, dust and scratches. They also have another use of absorbing the ultraviolet rays which often makes outdoor photographs hazy and indistinct.
Skylight Filter: Reduces the excessive bluishness that frequently occurs in outdoor colour photography, especially in open shade under a clear, blue sky. This means outstanding outdoor shots with superb colour balance and clarity under all conditions. Also keeps skin tones free of colored reflections from nearby objects such as the shade of trees.
Polarizing Filter: Eliminates reflections from none metallic surfaces such as water, glass ect. Also increases Contrast and colour saturation.
NDx2, x4, x8: Neutral Density filters are often ignored by photographers, but they have several uses and offer the possibility to achieve otherwise unachievable results. ND filters appear grey and reduce the amount of light reaching the film; they have no affect on colour balance.
They have four main uses:
i. To enable slow shutter speeds to be used, especially with fast films, to record movement in subjects such as waterfalls, clouds, cars, seas etc.
ii. To decrease depth of field by allowing wider apertures to be used, this helps separate subjects from their background.
iii. To decrease the effective ISO of high speed film (i.e.: above ISO400) and allow it to be used outdoors in blight situations.
iv. To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which would normally cause over-exposure.
Infrared Filter: Used for photography with infrared films. infrared film is also sensitive to ultraviolet rays and the shorter wavelengths of the visible spectrum so it is necessary to filter out all but the infrared rays.
R72 passes only infrared rays above 720nm; RM90 passes only that above 900nm. Often used in crime detection, medical photography, detection of distribution of vegetation, etc.
In ordinary photography with infrared film or infrared colour film, the Y (K2), O (G), R (25A) and other filters can also be used to change the contrast or colour effect.
Coloured Filters: As their names suggests, these filters use colored glass. They are used for colour correction of different light sources when using colour film, or for controlling contrast with Black & White film.
Colour correction filters are important as colour films do not have the flexibility of the human eye to automatically adjust to different situations. Black & White films register colours as shades of grey and the rendition of each colour in a scene is important, so filters can be used to control this.
Special Effect Filters: There are too many to go into on here so I will leave it for you guys to research but to cover the basics, these filters can add effects such as starbursts, close-ups, softening and multi-images. It is simple to achieve outstanding creative or unusual results and take special photographs for memorable occasions such as weddings, birthdays and holidays
Information courtesy of Hoya Filters (
http://www.hoyafilter.com/products/hoya/hoya-05.html)