4 Lens Filters for Digital Photographers
Since the introduction of photo-editing software, most lens filters have become obsolete. Filters, such as warming and cooling filters, are not required with post-processing software. Because photo-editing software cannot change how light is captured, a few filters are still required.
When researching for lenses to purchase, look at what filter size the lenses are; two popular sizes are 72mm and 77mm. Because filters can degrade image quality, high-quality filters are recommended to minimize degradation; high-quality filters cost around $100. Lenses with the same filter size will save money from purchasing several of the same filters.
Circular polarizing (CPL) filters deflect light as light passes through the filter. This will result in photographs that have little to no reflection of metallic surfaces, such as metal and water. In addition to eliminating reflections, CPL filters add saturation to photographs, famously giving outdoor images tremendously blue skies. Circular polarizing filters rotate, allowing the photographer to adjust the strength of the polarization.
Photographers use neutral density (ND) filters to reduce light. To facilitate motion blur, even with the lowest ISO and smallest aperture, photographers still may need to reduce light. Neutral density filters solely reduce light, leaving the image’s color unchanged. Frequent applications include pictures involving moving objects, such as rivers, oceans, and automobile traffic. Filters are designed by how many stops of light they block, ranging from .3-stop to 13-stops. The more stops on an ND filter, the more light that will be blocked, creating smoother motion blur from a longer shutter speed. Neutral Density filters are also used when a photographer wants to shoot with a wide aperture setting (f/2.8 for example) and there is simple too much light on the scene to accommodate the desired shutter speed.
A graduated neutral density (GND) filter reduces light for half of the filter. The filter is split between neutral density and clear sides, with a hard or soft edge separating them. When shooting against the sun, the photographer exposes for the sky or ground, but not both. The image will result in the ground properly exposed but the sky blown-out, or vice-versa. When using a GND filter, the photographer can expose for both: expose for the ground and use the neutral density half of the filter to darken the sky, resulting in a properly exposed image.
Photographers use ultraviolet (UV) filters to protect their lenses’ front elements; rarely do contemporary photographers purchase these filters to reduce UV radiation. Adding a UV filter can protect the front element in case of a collision. Ultraviolet filters, however, are not required because they are not used for aesthetics. Unlike other filters, which are only used in certain situations, UV filters can become expensive because most photographers purchase one filter per lens because the photographers always want their lenses to be protected. Any addition of glass between the scene and the camera sensor reduces quality. The advantage of protecting your lens VS a reduction in image quality is a heated topic among photographers.