12-05-2010, 01:33 AM
[quote name='Brightcolours' timestamp='1291480107' post='4760']
No, it does not show PF and LoCA happening. It only shows LoCA happening (magenta blur to the front, green blur to the back).
All lenses that show LoCA (most wider aperture lenses and macro lenses) have exactly the same thing: Green blur on one side of the focal plane, purple on the other side.
Check photozone's more current reviews to verify that.
PF only is one colour, and only around very bright areas. It also usually only radiates to one side of bright "holes", where LoCA is in the whole blur/bokeh.
BTW: The PF examples I have... the top one, from the Sony 16mm f2.8 fisheye, does not seem to be PF now that I looked at it again. It seems to be NORMAL (La) CA, with green edges going from the "dark" into the bright, and purple edges going from the bright into the dark. It was a corner crop, so I am pretty sure that is normal CA and not PF (and certainly not LoCA).
[/quote]
However the article (http://toothwalker.org/optics/chromatic.html) you provided as a reference actually says that purple fringing *is* LoCA?
No, it does not show PF and LoCA happening. It only shows LoCA happening (magenta blur to the front, green blur to the back).
All lenses that show LoCA (most wider aperture lenses and macro lenses) have exactly the same thing: Green blur on one side of the focal plane, purple on the other side.
Check photozone's more current reviews to verify that.
PF only is one colour, and only around very bright areas. It also usually only radiates to one side of bright "holes", where LoCA is in the whole blur/bokeh.
BTW: The PF examples I have... the top one, from the Sony 16mm f2.8 fisheye, does not seem to be PF now that I looked at it again. It seems to be NORMAL (La) CA, with green edges going from the "dark" into the bright, and purple edges going from the bright into the dark. It was a corner crop, so I am pretty sure that is normal CA and not PF (and certainly not LoCA).
[/quote]
However the article (http://toothwalker.org/optics/chromatic.html) you provided as a reference actually says that purple fringing *is* LoCA?