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Chromatic aberration also affects black-and-white photography. Although there are no colors in the photograph, chromatic aberration will blur the image. It can be reduced by using a narrow-band color filter, or by converting a single color channel to black and white. This will, however, require longer exposure (and change the resulting image).
1: Imaging by a lens with chromatic aberration. 2: A lens with less chromatic aberration. In optics, aberration is a property of optical systems, such as lenses, that causes light to be spread out over some region of space rather than focused to a point. [1]
For example, Newton noted that such chromatic dispersion causes the edges of a white object to be tinged with color. [14] Modern accounts of chromatic aberrations divide ocular chromatic aberrations into two main categories; longitudinal chromatic aberration (LCA), and transverse chromatic aberration (TCA). [14]
Chromatic aberration of a single lens causes different wavelengths of light to have differing focal lengths. An achromatic doublet brings red and blue light to the same focus, and is the earliest example of an achromatic lens. In an achromatic lens, two wavelengths are brought into the same focus, here red and blue.
Coma of a single lens. Each cone of light focuses on different planes along the optical axis. In optics (especially telescopes), the coma (/ ˈ k oʊ m ə /), or comatic aberration, in an optical system refers to aberration inherent to certain optical designs or due to imperfection in the lens or other components that results in off-axis point sources such as stars appearing distorted ...
In photographic and microscopic lenses, dispersion causes chromatic aberration, which causes the different colors in the image not to overlap properly. Various techniques have been developed to counteract this, such as the use of achromats , multielement lenses with glasses of different dispersion.
Examples of temporal aberrations include chromatic aberrations, energy spread, focal spread, instabilities in the high voltage source, and instabilities in the objective lens current. An example of a spatial aberration includes the finite incident beam convergence.
To minimise chromatic aberrations, e.g., in which different wavelengths of light are refracted to different degrees, requires, at a minimum, a doublet of lens elements with a positive element having a high Abbe number matched with a negative element of lower Abbe number.