Filters are a circular glass tool mostly made of high-quality glass (or resin) which is attached to the front of a lens, for various purposes, but mainly to enhance the picture or produce a desired effect on the picture. Filters are essential for better professional pictures (especially when it’s an outdoor shoot) and are of various types, all depending on your objective.
Types of Filters
1. Linear or Circular Polarizer Filters: – Primary use are to reduce glare and improve saturation. Common subject matter could include sky / Water / Foliage in Landscape Photography.
2. Neutral Density (ND) Filters: – These help in extending Exposure time and her primary subject are shooting Waterfalls, Rivers under bright light
3. Graduated Neutral Density Filters (GND): – These work to control strong light gradients, reducing vignetting. Primary subject is to capture dramatically lit landscapes.
4. Ultraviolet (UV) Filters: – These improve clarity with film. They also act to provide protection for the lens. These filters are widely and extensively used as they’re appropriate for any subject.
5. Warming/Cooling Filters: – These effect colour changes, mainly working to change the white balance of the picture. Their primary subjects could be when shooting landscapes, underwater or special effects type of shots.
Challenges of Using Lens Filters
Filters are an introduction of another set of glass, so they should be used mainly when necessary as they adversely affect the resulting image, maybe reducing it. This results usually comes in the form of either a slight color tint, a reduction in local or overall image contrast, or ghosting and increased lens flare, caused by light inadvertently reflecting off the inside of the filter. Filters may also introduce physical vignetting.
Choosing Your Filters
Choosing a Filter Filters come in two variants, Screw-on or Front fitters. The latter are better, because Screw-on maybe lens and diameter selective. The height of the filter edges may also be important. Ultra-thin and other special filters are designed so that they can be used on wide angle lenses without vignetting. On the other hand, these may also be much more expensive and often do not have threads on the outside to accept another filter (or sometimes even the lens cap).