A wide-angle lens converter attached to the camera using a lens adapter.
A polarizing filter (top) darkens the sky and removes reflections from foliage so it has more color. A shot without a filter is shown below.
Many lenses have threads into which you can screw filters and other accessories. The problem with some accessories is that they permanently change the image you capture. If you use a photo-editing program to get the same effect, you can have a "straight" unedited version and any number of edited versions. Here are just some of the accessories you can attach.
- Interchangeable lenses are available on all digital SLRs and digital rangefinder cameras.
- Lens converters extend the zoom range of cameras with a fixed zoom lens that cannot be removed. These converters screw in, or slide onto the zoom lens. One problem with these lenses is that they are camera-specific. They can be quite expensive and if you buy a new camera, even a new model of the same camera, the lens converters may not work with it.
- Lens collars surround a lens and have a tripod foot. This allows you to mount the lens to the tripod, rather than the camera body and this gives much better balance with longer lenses. Once attached to the tripod, you can loosen the collar to rotate the camera into a horizontal or vertical position while keeping it centered on the tripod. This eliminates the need to flop the camera
over to get vertically-oriented shots.
- Lens hoods protect the front element from bumps and keep stray light from striking the front of the lens and causing flare or ghost images. On point and shoot cameras, this function is sometimes fulfilled by a sliding cover.
- Caps protect the front and rear of the lens when it's not in use. A body cap protects the camera when no lens is attached.
- Protect filters keep the front element of your lens from getting scratched or dirty.
- Circular polarizing filters remove reflections from glass, water, and other reflective surfaces, darken blue skies, and improve color saturation. If you use a linear polarizing filter, you can't use autofocus. Because these filters block part of the light, exposures are increased by between 2 and 3 stops—referred to as the filter factor.
- Skylight filters reduce the blue casts you often get when photographing subjects in the shade on sunny days.
- UV filters absorb ultraviolet light and cut the haze when photographing landscapes or from airplanes.
- Neutral density filters cut the light entering the camera so you can use slower shutter speeds or wider apertures in bright light. This helps you get softer backgrounds in portraits and better capture flowing water. A few cameras have a command that lets you get this same effect digitally, without using a filter.
- Soft focus filters soften the focus to make portraits more flattering and to make hazy, romantic landscapes.
- Close-up lenses magnify the subject without affecting aperture settings.
- Color conversion filters let you fine-tune the way you capture colors. These have been made irrelevant on cameras what give you fine control over white balance.