Canon® EOS Digital Photography Photo Workshop

5.2. LENS FLARE

Lens flare is the result of unwanted light entering the lens and hitting the image sensor. How the effect occurs depends upon various factors such as the number of internal lens components, lens focal length, aperture size and width, and the type of light source and its brightness (such as the sun, a spotlight, etc.).

Sometimes the effect of lens flare can be interesting, providing an artistic quality to the photo.

Many higher-quality lenses have features that help deter flare and disperse light within the lens before it reaches the sensor, but, as with ghosting, virtually any lens is susceptible to flare given the right conditions. The appearance in the image is that of a series of geometric bright shapes that extend from a corner of the image toward the center, gradually increasing in size. They can look like starbursts, rings, or polygons that are a direct reflection of the lens's aperture shape. Sometimes, it can simply be the effect of a hazy quality to the lens (see figure 5-1). Longer lenses and lenses with more complex optical systems and multiple elements tend to suffer from flare more severely than simpler, shorter ones; however, it can happen in virtually any lens given the right light conditions.

Figure 5-1. Lens flare and ghosting can both have similar effects caused by unwanted light entering your lens at an extreme angle. This type of hazy look ...