Author Topic: Chromatic aberration tool doesn't check image contrast?  (Read 769 times)

obetz

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Chromatic aberration tool doesn't check image contrast?
« on: May 05, 2017, 03:55:14 pm »
Hi All,

chromatic aberrations arise at high contrast edges.

Can it be that the DxO CA tool does not limit the removal to high contrast edges but desaturates every small red element in the image, e.g. a red brake light on a dark car?

Oliver

htran

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Re: Chromatic aberration tool doesn't check image contrast?
« Reply #1 on: May 05, 2017, 04:15:55 pm »
Hello,
This is a good example to improve. May you share us your image? it can help us to analyse.

Regards,
HT

obetz

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Re: Chromatic aberration tool doesn't check image contrast?
« Reply #2 on: May 05, 2017, 07:52:52 pm »
See the red umbrellas in the attached snippets.

obetz

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Re: Chromatic aberration tool doesn't check image contrast?
« Reply #3 on: June 20, 2017, 10:51:55 am »
here another example, DXO_CA_off.jpg is without CA correction, DXO_CA_marked.jpg is with CA correction and has green circles around some examples of bad artifacts.

DXO_CA.gif is an animated GIF toggling CA correction on and off. You need to click on the preview image to see the animation!

Customer support wrote that this is just some desaturation but no removal of detail, and I should compensate by using more vibrancy.

I'm not satisfied.

Oliver

Fotoguido

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Re: Chromatic aberration tool doesn't check image contrast?
« Reply #4 on: July 28, 2017, 08:13:27 pm »
First I would not consider these CAs as relevant to be removed. But if you do, try to play around with size slider (0-12) and intensity. DXO Support is right, increasing vibrancy can help. In most cases I solve those problems like this.

BUT:

You are also right, DXO CA removal is not perfect, in drastical and very rare cases (very different from all examples posted here) I help myself by using Capture NX-D to remove CAs as a first step, it works perfectly by just a klick and lets non CAs unconsidered (something DXO can really learn from! --> Guys, please!?).

If you take Capture to remove CA, be aware to also apply de-noising as appropriate , check colours and switch off everything else before converting to TIF and continue with DXO, it can not handle PRIME-denoising and colours such as Camera profiles from TIFs. Maybe you also need to play around a bit with Sharpness, can be a bit tricky. Everything else will be just fine then. (Sadly do not have an example handy)

Greetings to the community!
Guido

P.S.: I am not a fan of CNX especially due to ist weired handling, at this point DXO is unbeaten!!

 

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