Photograph of NASA lunar lander containing lens flare. Besides the obvious flare around the Sun, the light artifacts at the bottom right are also caused by flare.

Lens flare is the light scattered in lens systems through generally unwanted image formation mechanisms, such as internal reflection and scattering from lens inhomogeneities. These mechanisms differ from the intended image formation mechanism that depends on refraction of the image rays. For good optical systems, and image flare is a secondary effect and generally not visible. But when an image includes a very bright light source, flare generated by a bright image region can have enough intensity to scatter a visible amount of light. The unwanted scattering superimposes broadly across the image and adds light to the dark image regions, reducing the overall image contrast. Download high resolution version (900x905, 158 KB)Sample of lens flare. ... Download high resolution version (900x905, 158 KB)Sample of lens flare. ... NASA logo Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ... The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program to achieve the transit from Moon orbit to the surface and back. ... For other uses, see Sun (disambiguation). ... A lens. ... The reflection of sunlight on water Reflection is the abrupt change in direction of a wave front at an interface between two dissimilar media so that the wave front returns into the medium from which it originated. ... In particle physics, scattering is a class of phenomena by which particles are deflected by collisions with other particles. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength. ...

Lenses with large numbers of elements such as zooms tend to exhibit greater lens flare, as they contain multiple surfaces at which unwanted internal scattering occurs. A Canon Inc. ...

The spatial distribution of the lens flare typically manifests as several starbursts, rings, or circles in a row across the image or view. Lens flare patterns typically spread widely across the scene and change location with the camera's movement relative to light sources, tracking with the light position and fading as the camera points away from the bright light until it causes no flare at all. The specific spatial distribution of the flare depends on the shape of the aperture of the image formation elements. For example, if the lens has a 6-bladed aperture, the flare may have a hexagonal pattern. In optics, an aperture is something which restricts the diameter of the light path through one plane in an optical system. ...

Such internal scattering is also present in the human eye and manifests in an unwanted veiling glare that is apparent when viewing very bright lights or highly reflective (e.g., specular) reflections.

Lens flare is extremely difficult to control when a bright light source like the sun is just outside the frame.

When a bright light source is shining on the lens but not in its field of view, lens flare appears as a haze that washes out the image and reduces contrast. This can be avoided by shading the lens (the purpose for which lens hoods are designed). In a studio, a gobo can be attached to the lighting to keep it from shining on the camera. Modern lenses use lens coatings to reduce the amount reflection and minimize flare. Princes Street and the Castle Rock at twilight. ... Princes Street and the Castle Rock at twilight. ... A lens hood used on the Canon EF 70-200mm lens In photography, a lens hood is a device used with lenses to block the sun to prevent sun glare. ... Projected light shines through a Gobo and onto a screen for decorative, informational or dramatic effect. ...

Artificial lens flare is a common effect in various graphics editing programs, although its use can be a point of contention among professional graphic designers. During the mid- to late-1990s, lens flare was a popular graphical gimmick for computer and video games. Graphic design is the applied art of arranging image and text to communicate a message, or facilitate understanding. ... A computer game is a game composed of a computer-controlled virtual universe that players interact with in order to achieve a defined goal or set of goals. ... A computer game is a game composed of a computer-controlled virtual universe that players interact with in order to achieve a defined goal or set of goals. ...

External links

• Lens Flare - Understanding flare and techniques to reduce it.