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Advice needed on removing chromatic aberrations - Printable Version

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Advice needed on removing chromatic aberrations - Guest - 06-25-2011

Hi,



Recently I made the attached picture. It doesn't look too bad at this size, but a 100% crop (also attached) shows some serious chromatic aberrations around the light branches/grasses.



The photo was taken with a Canon EF 100-300mm F/4.5-5.6 USM. Chromatic aberrations are one of the weaknesses of this lens, according to the test on this site. But that same test also says: "Nonetheless lateral CAs can be corrected or at least reduced via imaging tools like Photoshop".



Can anybody give me some advice how to do this? I have tried with both Photoshop CS5 and Canon DPP 3.9.3.0, with little result. With Photoshop I seem to be able to practically remove the red fringe from either one or the other side of a branch, but not from both, using the chromatic aberrations slider in Camera Raw. In Canon DPP I cannot get any improvement.



Thomas


Advice needed on removing chromatic aberrations - Guest - 06-25-2011

This isn't lateral CA, therefore it's not possible to remove it with tools designed to remove lateral CA.

Try this instead: http://www.photographerstripod.com/Articles/ViewArticle/tabid/72/smid/437/ArticleID/25/reftab/70/t/Photoshop-How-to-Remove-Purple-Fringing/Default.aspx

You may have to use layer mask to avoid colour shifts in the rest of the photo.



Ciao, Walter


Advice needed on removing chromatic aberrations - Guest - 06-25-2011

Walter,



Thanks! That works quite well. I do need a layer mask, I think because the animal itself has a color rather similar to the fringing.



Tom





[quote name='Walter Schulz' timestamp='1309002185' post='9519']

This isn't lateral CA, therefore it's not possible to remove it with tools designed to remove lateral CA.

Try this instead: http://www.photographerstripod.com/Articles/ViewArticle/tabid/72/smid/437/ArticleID/25/reftab/70/t/Photoshop-How-to-Remove-Purple-Fringing/Default.aspx

You may have to use layer mask to avoid colour shifts in the rest of the photo.



Ciao, Walter

[/quote]


Advice needed on removing chromatic aberrations - Brightcolours - 07-01-2011

A much easier way, I find (because the colour(band) selection is so much more precise), is the "Image/Adjustments/Replace Color..." function from Photoshop. With the color dropper and the +/- dropper tools you can get a very precise selection, and you get great feedback when you desaturate and/or change hue. You can make a simple lasso selection over the part where you want to address a certain colour artifact.