[quote name='wim' timestamp='1337459011' post='18339']
Longitudinal Chromatic Aberration, LoCA, or Spherochromatism (which is the proper term), only occurs in the OOF areas, and consists of a magenta part in the OOF foreground area, and cyan in the background OOF area at high contrast transitions.[/quote]
There is no single plane of focus, unless you have a perfectly corrected lens. Any single plane will not have all colours simultaneously in focus. The apparent plane of best focus will still allow colour aberrations to form on it, if the contrast is strong enough to make it visible.
I proposed a simple way to disprove this as a mechanism, and so far I have not yet seen a single sample that would do so. Find a shot where there is a clear plane of best focus, and purple fringing on objects clearly behind it that can not be explained by lateral CA.
Longitudinal Chromatic Aberration, LoCA, or Spherochromatism (which is the proper term), only occurs in the OOF areas, and consists of a magenta part in the OOF foreground area, and cyan in the background OOF area at high contrast transitions.[/quote]
There is no single plane of focus, unless you have a perfectly corrected lens. Any single plane will not have all colours simultaneously in focus. The apparent plane of best focus will still allow colour aberrations to form on it, if the contrast is strong enough to make it visible.
I proposed a simple way to disprove this as a mechanism, and so far I have not yet seen a single sample that would do so. Find a shot where there is a clear plane of best focus, and purple fringing on objects clearly behind it that can not be explained by lateral CA.
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