Vignetting in digital photography is when the area near the outside of your photo appears to be less bright than the center area. A vignette often appears as an irregular ring or oval circling your picture. A vignette can be barely perceptible or easily seen. There are four distinct types of vignetting. Some can be used to create interesting digital photos, while other types, which you should avoid, could be caused by equipment and other reasons.
You can create vignettes in your digital photos with the use of various photo-editing software programs. Its primary application is portraits. A vignette can help to highlight the subject, but you should use this technique sparingly. It was used during the early years of photography, but it no longer works well in the digital age. Subtle vignetting could also emphasize a silhouetted subject or object.
Some of the light entering the lens of your camera may cause vignetting of your digital photos because of the angle the light strikes the sensor. This may relate to where you are standing to take a picture, the direction of the light source or the time of day when shooting outdoors. You may notice this effect, especially if you use an inexpensive point-and-shoot camera. Pictures taken with a wide-angle lens will often include some natural vignetting, but it seldom occurs with zoom lenses that are of a particular focal length or greater.
This simply means that you’re using your camera and lenses in such a way that less light can enter. For example, you may have the wrong kind of lens hood attached to the front of the lens, or it isn’t attached correctly. Sometimes, you’ve added too many filters or are shooting with extension tubes. Then, you try to take digital photos at a small aperture, or lens opening, maybe f/16. That just accentuates the unintentional vignetting. Open the lens farther to let more light in the camera, which will help to reduce the vignetting.
Even though your camera lens appears to be a clear path through glass elements to the sensor, the multiple layers of elements in many high-end lenses actually inhibit the amount of light that enters your camera. By the time the light reaches the sensor to register your digital photo, the light on the edges are not as strong as those in the center. When you use a lens with very large aperture opening options, such as f/1.4, f/2 or f/2.8, more of the light enters the camera and hits the border area of the image sensor. In most cases, any vignetting will disappear.