File:Nearsighted color fringing -9.5 diopter - Canon PowerShot A640 thru glasses - overview.jpg

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Description
English: Example of how extremely nearsighted people experience color fringing and distortions if not looking directly through the center of their glasses.

See also:

Cropped close-up view of fringing
Test bitmap used to create these examples.

This was created by setting the manual zoom on a Canon PowerShot A640 to be nearsighted, then pointing the camera through the eyeglasses turned backwards to correct the intentional myopia of the camera lens.

Wide view image. Next image is a closeup crop of color fringes.

Through the sides of the lens, the colors are prismatically shifted and distorted, resulting in seeing color fringing that does not exist. These color fringes make accurate and precision drawing and painting difficult for a person wearing glasses.

Several color-box positioning mistakes were made while trying to create the example image for this demonstration. Only zooming in at high detail to enlarge edges is sufficient for dealing with these optical color errors.

Extreme nearsighted users of contact lenses do not see these color fringes because the contact lens moves with the cornea and color rendering is always done through the center of the contact lens.

(Presumably, optical materials of lower index can result in better color rendering, however I have been unable to find a source for pure glass eyeglass lens to verify this claim.)
Русский: Иллюстрация аббераций (дисторсия, кривизна поля, хроматическая абберация), создаваемых оптической системой (в примере - очками с отрицательными линзами)
Source Own work
Author DMahalko, Dale Mahalko, Gilman, WI, USA -- Email: dmahalko@gmail.com

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current05:03, 14 October 2009Thumbnail for version as of 05:03, 14 October 20093,648 × 2,736 (2.91 MB)commons>DMahalko{{Information |Description={{en|1=Example of how extremely nearsighted people experience color fringing and distortions if not looking directly through the center of their glasses. Wide view image. Next image is a closeup crop of color fringes. Throug

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