Lens flare
Lens flare ( English lens flare = 'Linsen-Lichtschein') is the bright image of the light source in the form of the iris diaphragm, which is created by reflections on one or more lenses in the lens . The German name is lens flare or lens reflection .
photography
With a few exceptions, the number of lens flares in the image corresponds to the number of lenses in the lens. Their shape corresponds to the shape of the iris diaphragm and can thus, depending on the number of diaphragm blades , be triangular or polygonal and, depending on the shape of the blades , be ring-shaped or star-shaped. The lens flares can be many times brighter than the subject and thus lead to a decrease in contrast . The color of the lens flares is largely influenced by the anti-reflective coatings on the lenses.
In classic photography, lens flares are suppressed by suitable aids such as lens hoods and / or polarization filters in order to improve the image quality. However, filters usually tend to create additional lens flares. In artistic recordings, lens flares are sometimes used deliberately to make the brightness of a light source perceptible for the viewer.
Use as a stylistic device
Lens flares are used in photography and film to create a certain mood. Since the brightness of a cinema screen or a photograph is far below the brightness of a light source such as the sun, the impression of extreme brightness must be conveyed through the use of lens flares. With wide-angle or anamorphic lenses, the lens flares play a particularly important role, since light sources outside the image often lead to lens flares. A good example of the use of lens flares is the 2013 film Gravity , which shows the great differences in brightness between deep black space and glaring sunlight. In the films Star Trek (2009) and Total Recall (2012) the effect was also used very often - sometimes so massively that it was even mentioned negatively in many reviews. Another example of excessive use of the effect is the Star Trek: Discovery series .
In some cases, image disturbances of this kind are deliberately included in computer-generated ( rendered ) images or film sequences in order to make them appear more realistic. For this reason, many computer games also generate lens flares.
Web links
- Pictures of lens flares at www.lens-flare.de ( Memento from October 12, 2017 in the Internet Archive )
- Explaining the formation of flare and instructions on their suppression (English)