# Removing white Edge fringing



## raybark (Feb 24, 2014)

Am processing from RAWs in LR4 and on parts of buildings I can see thin white fringes where the walls of the building are against a strong blue sky. It doesn't seem like CA because there is no colour showing in the fringes. I have clicked 'Remove CA'. Is there a way of eliminating the fringes in LR or should it be corrected in PS?


----------



## DaveS (Feb 24, 2014)

Hello Raybark.

  What processing are you doing to your pictures?  How much are you pushing the contrast up?


----------



## Hal P Anderson (Feb 24, 2014)

Welcome to the forum. Any chance that you've applied strong sharpening to the image?


----------



## raybark (Feb 24, 2014)

DaveS said:


> Hello Raybark.
> 
> What processing are you doing to your pictures?  How much are you pushing the contrast up?



I used the precept called 'Punch' and sharpened to 40%. Didn't touch the contrast slider.


----------



## Hal P Anderson (Feb 24, 2014)

Hmmm...is the fringe still there when you remove all your processing from the image? Just hold down the shift key and hit the button on the lower right that will then read 'Reset(Adobe)' (You can easily undo this in the History panel.)


----------



## raybark (Feb 24, 2014)

Thanks for that suggestion Hal. Afraid the fringing is still there after the reset so it looks as if it's produced in camera? I used a Sony RX100 shooting Raw, hand held but it looks sharp enough. The fringes are only on the wall edges in shadow. Ray.


----------



## Tony Jay (Feb 24, 2014)

Hi Ray, your issue is not CA.
This is a well known phenomenon where, along sharp edges blue (normally sky) meets with something else (usually rocks or mountains, in my case) that has a lot of yellow/orange the result is a thin but very distinct white fringe.
A lot of global tonal or colour edits done in Lightroom will accentuate the phenomenon but they don't cause it.

I have not found a fix in Lightroom but it is easily fixable in Photoshop.
If you want a technique to fix it I can think of no better a reference than Jeff Schewe's recent books, "The Digital Negative" and "The Digital Print".
If memory serves he deals explicitly with this issue in "The Digital Negative" with a step-by-step description for the fix using masks and mask inversion.

Tony Jay


----------



## raybark (Feb 24, 2014)

Thanks Tony. Your description of the problem fits exactly how it looks. I will follow up your Photoshop suggestion.  Ray


----------



## Tony Jay (Feb 24, 2014)

You are welcome - let us know how you go.

Tony Jay


----------



## raybark (Feb 28, 2014)

Tony Jay said:


> You are welcome - let us know how you go.
> 
> Tony Jay



Hi Tony, I bought Jeff Schewe's book, The Digital Negative and he has what he calls a "Blue Edge Fix". Images showing the problem in his book look just like mine so thanks for the link. His solution is to paint along the edges with the Clone Stamp tool whilst in the inverted sky channel. He admits this is tedious (I agree!) but it seems to be the only solution and it works. So I not only have a solution but also some great 'bedtime reading'. Thanks again.  Ray


----------

