Correcting image distortion and noise – Adobe Photoshop CC 2014 v.14.xx User Manual
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Correcting image distortion and noise
Correction
About lens distortion
Correct lens distortion and adjust perspective
Reduce image noise and JPEG artifacts
About lens distortion
Barrel distortion is a lens defect that causes straight lines to bow out toward the edges of the image. Pincushion distortion is the opposite effect,
where straight lines bend inward.
Examples of barrel distortion (left) and pincushion distortion (right)
Vignetting is a defect that darkens the corners of an image due to light falloff around the perimeter of the lens. Chromatic aberration appears as a
color fringe along the edges of objects, caused by the lens focusing on different colors of light in different planes.
Some lenses exhibit different defects at certain focal lengths, f-stops, and focus distances. With the Lens Correction filter, you can specify the
combination of settings used to make the image.
Correct lens distortion and adjust perspective
The Lens Correction filter fixes common lens flaws such as barrel and pincushion distortion, vignetting, and chromatic aberration. The filter works
only with 8- and 16-bit-per-channel images in RGB or Grayscale mode.
You can also use the filter to rotate an image or fix image perspective caused by vertical or horizontal camera tilt. The filter’s image grid makes
these adjustments easier and more accurate than using the Transform command.
Automatically correct image perspective and lens flaws
Using lens profiles, the default Auto Correction option quickly and accurately fixes distortion. For proper automatic correction, Photoshop requires
Exif metadata that identifies the camera and lens that created the image, and a matching lens profile on your system.
1. Choose Filter > Lens Correction.
2. Set the following options:
Select the problems you want to fix. If corrections undesirably extend or contract the image beyond original dimensions, select
Auto Scale Image.
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