« Back to Dictionary Index

Barrel distortion is a type of optical or electronic image distortion characterized by the curvilinear deformation of straight lines within the image.

Characteristics:

  1. Shape of Distortion:
  • In barrel distortion, horizontal and vertical straight lines appear curved outward, resembling the shape of a barrel.
  • This effect causes lines that should be straight to appear bowed or bulging towards the edges of the image.
  1. Positive Distortion:
  • Barrel distortion is also known as positive distortion because it results in an expansion or bulging effect towards the image edges.
  1. Causes:
  • Optical Lenses: It often occurs in images captured with wide-angle lenses or fisheye lenses, where the angle of view is extensive, causing light rays to refract differently.
  • Software Correction: In digital imaging, barrel distortion can also occur due to image processing algorithms or wide-angle correction methods.

Examples and Usage:

  1. Photography:
  • Barrel distortion is commonly seen in photographs taken with wide-angle lenses, especially at the extremes of the lens’s field of view.
  • It can distort architectural lines, making buildings appear curved or bent at the edges.
  1. Computer Graphics:
  • In computer graphics and digital imaging, barrel distortion might occur when rendering scenes or manipulating images with wide-angle effects.

Correction:

  1. Lens Correction Profiles:
  • Many image editing software tools offer lens correction profiles that can automatically or manually correct barrel distortion.
  • These corrections adjust the image to minimize or eliminate the bulging effect, restoring straight lines to their proper shape.
  1. Adjustment in Post-Processing:
  • Photographers and designers often use software tools to manually correct barrel distortion by adjusting geometric distortions and perspective.

Barrel distortion is a common optical phenomenon in which straight lines in an image appear curved outward towards the edges. It is often associated with wide-angle lenses and fisheye lenses but can also occur in digital imaging processes. Understanding and correcting barrel distortion is essential in photography, graphic design, and other fields where accurate representation of perspective and geometry is crucial.

« Back to Dictionary Index