Occurs when light rays travels through glass (or lens). Each light wave frequency bends (refracts) at a different angle while traveling through the lens. Short wavelengths (toward the blue) are refracted more than long wavelengths (toward the red). Thus, different color wavelengths are exposed on different portions of the photosensitive material (film or sensor). Achromatic lens solves this problem by combining lenses with different refractive indexes. Comments & Discussion
The inability of a lens to focus different colours on the same focal plane. Appearing as a 'colour fringe' around objects, especially at the edges of the photograph.
Also known as the "purple fringe effect." It is common in two Megapixel and higher resolution digital cameras (especially those with long telephoto zoom lenses) when a dark area is surrounded by a highlight. Along the edge between dark and light you will see a line or two of purple or violet coloured pixels that shouldn't be there.
Lens aberration that focuses different colors of light at different angles.
False color, or secondary spectrum, induced by refracting telescopes. Manifests itself in the form of a blue or purple halo around bright objects. See achromat, apochromat.
The discoloration of a bright object caused by dispersion in a refracting telescope's objective lens(es). This dispersion causes different colors of light to come to a focus at different distances.
Is a distortion of the picture that is caused by the light not being focused properly. This is caused by the lens system spreading the light like a rainbow. This is only found in displays the use lenses to project the image. Calibration cannot influence this, but display selection can. Typically more expensive display devices use higher quality lenses to reduce this effect. Chroma Delay - Is a video artifact that appears as the color information shifted to the left or right of the black and white. This is caused by timing errors in the signals.
In refractor telescopes, which use lenses to bend the light, different wavelengths of light bend at different angles. This means that the stars you see will usually have a blue/violet ring around them, as this light is bent more than the rest of the spectrum. It is not present at all in reflectors, nor to any significant degree in catadioptrics. Different glasses and crystals (notably fluorite) are sometimes used to compensate for the aberration. Such telescopes are termed "achromatic," or "apochromatic" if the correction is is nearly perfect.
Image aberration. The image emerges with coloured margins.
Chromatic aberrations are caused by the lens in a refracting telescope failing to focus different wavelengths of light (i.e. the different colours of the spectrum that make up white light) onto the exact same focal plane (i.e. it focuses them at slightly different distances). It's effect is to create a purple blurring on the images. Today this is overcome by either using a double lens or, in large telescopes, by using process of reflection (mirrors) rather than refraction (lenses).
defect in an optical system which is the failure to bring different wavelengths to a common focus.
A lens defet that causes colors to focus at different distances from the lens, which results in a halo effect.
An error when different wavelengths of light bend differently through a lens, causing the focal point to be scattered
a defect in the images from refractor telescopes that is caused by different colors of light focussing to different points behind the glass lens. A rainbow of colors is produced around the image.
A prismatic effect in an image produced by an optical instrument, caused by the tendency of lenses to disperse light, or to refract different colors of light by unequal amounts, thereby turning a point of light into a very small spectrum, and causing the image of an extended object to become less sharp, and fringed by the end colors of the spectrum.
an optical aberration in which the image has colored fringes
Color artifacts due to inability of lens adjust light frequencies.
An aberration of refractive optical systems in which light is dispersed into its component colours, resulting in false colour in the image.
An optical defect in which not all colors come to focus at the same point, commonly associated with refractors. Typically seen in the eyepiece as a blue or purple fringe around bright objects. Back to top of glossary
The inability to bring light of all colors to the same plane of focus.
When light passes through a lens, such as in a refracting telescope, the various wavelengths of light, from red to blue, do not all focus to the same point. It can be eliminated by using an apochromatic lens which causes all visible wavelengths to focus back to one point.
Color shifts and color artifacts in an image caused by faults in a lens, or by the camera’s inability to register all three channels of color information. Single-chip video cameras are especially prone to chromatic abberation. Chrominance The saturation and hue of a video signal. Although slightly different in meaning, this term is often used interchangably with the term chroma to refer to color.
an optical defect caused by a single lens splitting up the incoming light (as does a prism) into its constituent colours and spoiling the image as each colour focuses at a different distance from the screen.
Purple fringing that occurs along the edges of backlit subjects such as plants, people, and buildings. Chromatic aberrations occur when the camera lens can't focus the different wavelengths of light onto the same spot on the image. Notice the purple light along the edges of the bars on the picture to the right.
Describes an optical lens defect, which causes different colours or wavelengths of light to be focused at different distances. It is seen as colour fringes along edges and around every point in the image.
Because lenses and prisms deviate blue light more than red light, a rainbow effect or colour spread will result unless achromatic combinations of optics are used to correct it.
This is a distortion of an image which occurs in refracting telescopes. It is caused by the fact that the path the light takes through the lens is dependent (very slightly) on the wavelength, that is the colour, of the light. This means that the colours are split and the image is 'smudged'. This effect is one of the reasons why reflecting telescopes, which do not suffer this effect, are preferred to refracting telescopes in modern astronomy. See also spherical aberration.
This aberration is found in telescope systems with lenses, but is generally associated specifically with refractors where it is most noticeable. In a refractor, light passes through a lens and is bent to reach a focus point. Each wavelength of light is bent differently, so they do not all meet at the same point of focus. The result is an out-of-focus glow, usually purple in color since the violet light is least likely to meet focus with the other colors. Some refractors are specially corrected for this aberration. CCD cameras are far more sensitive to ultraviolet and infrared light than the human eye, so only the very best refractors are suitable for high-resolution CCD imaging.
The failure of an optical system to focus different wavelengths (colors) of light at the same point, resulting in color fringes within the image.
A defect of optical lenses. Different wavelengths of light have different refractive properties. Therefore, an optical lens will different wavelengths of light to focus at different points. This produces colorful halos around bright stars and planets and a reduction in contrast, the visible effects of chromatic aberration.
An optical problem cause by light going through a refractor lens and not all the light frequencies coming to focus at the same point. Usually it is apparent at high magnifications as rainbow edges on objects. An apochromatic lens system is design to solve chromatic aberration.
Development flaw brought about by light being split (according to wavelength) by a lens, and thereby not hitting the correct point on the film. This causes blurriness and color irregularities.
The prismatic color separation of light as it passes through a lens. This is an imperfection in a lens.
A defect in simple lenses which causes false colours due to different wavelengths of light not being brought to a common focus.
Aberration due to different light colors (i.e. different wavelengths).
The dispersion of colors arising from unequal refraction of light of the different wavelengths of the spectrum. This defect of an optical system causes the image to be surrounded by a halo of colors. It is corrected in an achromatic lens system.
An unfocused or fringed appearance in an image caused by a lens' inability to focus different color wavelengths onto the same plane on the camera's film or sensor.
An aberration in an optical system that causes light of different colours to be focused in different planes.
A defect of simple lenses that causes the light rays of different colors to focus at different planes resulting in images being fringed or haloed with extraneous color.
The inability of a lens to bring all light wavelengths (particularly red & blue) into the same plane of focus, thus causing overall blur. Usually found in regular large-aperture telephoto and super-telephoto lenses. Not improved by reducing aperture size. Can be corrected with low dispersion (ED, LD SD) glass.
A type of distortion in lenses whereby the lens will bend light of different colors by unequal amounts. A well-made lens reduces this problem.
Purple fringing that occurs because the image sensor doesn't capture the different colors (wave lengths) on the same focal plane through the lens. Can be caused by the lens optics.
or Axial chromatic aberration - different wavelengths of light coming into focus in front of and behind the film plane, resulting in points of light exhibiting a rainbow-like halo and reduction in sharpness
is an error in lenses which causes the focal point to be scattered. This occurs because different wavelengths of light bend differently through a lens. A combination of lenses are required to minimize this error.
Also known as color fringing, this problem is caused when the camera lens do not focus the different wavelengths of light onto the exact same focal plane. It usually happens around subjects with a wide contrast and around the edges of the image in wide-angle shots.
An optical defect of a lens which causes different colors or wave lengths of light to be focused at different distances from the lens. It is seen as color fringes or halos along edges and around every point in the image.
The failure of a lens to bring light of different colors to the same focus.
the dispersion of light in lenses causes different colors to be focused at different places, causing the image to appear ringed with color.
an effect that occurs in some refracting telescopes. The glass lenses make different wavelengths of light bend at slightly different angles, with shorter wavelengths (blue) bent more. The effect can be noticed as a slight blue ring or rainbow effect. Reflecting telescopes do not have this problem. See the Astro 201 page on telescopes to see examples of refracting and reflecting designs.
A lens aberration which produces a blurred image. The lens has the inability to bring all wavelengths of light (especially red and blue) into the same plane of focus. Usually present in regular large-aperture telephoto and super-telephoto lenses. Basically, this aberration is caused by light rays of different wavelengths coming to focus at different distances from the lense. Blue will focus at the shortest distance and red at the greatest distance. Since the natural rays of light are a mixture of colors, each aberration will give a different value corresponding to each color thus producing blurred images.
inability of a lens to bring light from the same subject plane but of different wavelengths to a common plane of image or focus.
In photographic or lithographic process lens, the result of the unwanted dispersion of light so that colors of the white light spectrum are focused on slightly different distances on a single plane. Lenses which have been corrected for this problem are said to be achromatic.
A distortion found in refracting telescopes because lenses focus different colors at slightly different distances. Images are consequently surrounded by colored bands.
A defect of a lens that creates a fringe of colour round an object.
In optics, chromatic aberration is caused by a lens having a different refractive index for different wavelengths of light (the dispersion of the lens). The term "purple fringing" is commonly used in photography, although not all purple fringing can be attributed to chromatic aberration.