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View Full Version : Colour fringing correction on 9-18 micro images


Rens
12th September 2010, 08:38 AM
I'm using the Oly 9-18 on a Panasonic GH1, I love its compactness. Generally I'm very happy with it. I'd read the chromatic aberration at wide angle comments but not found it a problem until shooting figures silhouetted against the sky.

Using RAW files and ACR I can virtually eliminate the colour fringing both at the edge of the frame and some way in from the edge. But I need different correction to do this so I'm left with the option of cleaning one up completely at the expense of the other or compromising so that neither is perfect.

Not a major problem, but is there an obvious solution?

I should say my Photoshop skills are somewhat limited.

Rens

Alan Clogwyn
12th September 2010, 06:11 PM
I personally find that a global removal is not possible without affecting something else in the image. In PSP, what I do is to select a colour next to the fronged area, IE the colour that the fringe should have been, and set the paintbrush match mode to colour and then just draw over the fringed area very carfeully, it can take an age, but if a job's worth doing and all that.

Purple fringing is sometimes a case of jus tglobally turning the saturation of the magenta chanel all the way down to grey, but it depends on the subject matter, as obviously anything else magenta will also become grey.

Normally however I get red and blue fringes on opposite sides of the subject, which is tackled as orignially described.

xp1
12th September 2010, 06:45 PM
HI
There are a number of ways of correcting these types of faults.
If it affects the edges of objects then using one of the selection tools to select the area around the edge that has the fringing works well. After selecting the area use the colour controls to reduce the offending colour ie magenta or whatever. You will only reduce the colour in the selected and not the whole image.
Using duplicate layers of your image you can work on each area seperately then flatten layers when finished. WARNING always work on a copy of your original image.
This works inPSP as well.
Hope this helps.