Image Processing Reference
Figure 6.5 (left) A fairly large adjustment of +55 to the Fix Blue/Yellow Fringe slider has reduced the color fringing in this image
to an acceptable amount. (right) The adjusted image with all color channels visible shows a much cleaner edge along the flower
Seeing exactly what has changed may be difficult. A side-by-side comparison of
the image should help you see the greatly improved definition between flowers and sky.
Figure 6.6 shows the original along with the corrected image.
Figure 6.6 (left) Before the Chromatic Aberration is corrected, the image has color fringing along the edges of the flowers. (right)
After the correction, the definition between flower and sky is much better.
Vignetting, or darkening of the edges, is a fairly uncommon problem for most digital
cameras. It occurs when the light hitting the edge of the sensor isn't as strong as the
light hitting toward the center. It's more likely to occur at wide apertures and with full-
frame sensors such as the Kodak Pro SLR and Canon 1Ds.