Aberration
In photography, aberration refers to any deviation in the lens from ideal behavior, resulting in distortion or other imperfections in the image. Aberrations can occur for a number of reasons, such as lens design, manufacturing defects, or external factors like temperature or humidity.
There are several types of aberrations that can affect photographic images, including:
Chromatic aberration: This is caused by differences in the way that different wavelengths of light pass through a lens. It can result in colored fringes around edges in an image, particularly in high-contrast areas.
Spherical aberration: This occurs when light rays passing through different parts of a lens are not focused at the same point, resulting in a blurry or distorted image.
Coma: This is a type of spherical aberration that causes point sources of light to appear as streaks or “comets” in the image.
Distortion: This refers to any type of non-uniformity in the image, such as barrel distortion (where straight lines appear curved towards the edges of the frame) or pincushion distortion (where straight lines appear curved away from the center of the frame).
Aberrations can have a significant impact on the quality of a photographic image. They can cause images to appear soft, blurry, or distorted, and can make it difficult to achieve sharp focus or accurate color reproduction. However, modern lens designs and manufacturing techniques have greatly reduced the impact of aberrations on photographic images.
Photographers can also use software tools like Adobe Photoshop or Lightroom to correct aberrations in post-processing. These tools can help to reduce or eliminate chromatic aberration, distortion, and other imperfections in an image.
In summary, aberration is a term used in photography to describe any deviation in a lens from ideal behavior, resulting in distortion or other imperfections in the image. Understanding the types of aberrations and their effects can help photographers choose lenses and techniques that minimize their impact on image quality.