Chromatic Aberration correction


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Doug
Chromatic Aberration correction

If a way is ever figured out how to add new tools, I'd sure like a tool to do some basic correction of lateral CA. My EF-S 17-85 has trouble keeping the reds in line at shorter focal lengths, and sharpening loses some of its effectiveness when the pixel channels are skewed.

SFA
Doug,

Doug, FWIW I used multiple B&W tools, each with a very narrow band of a slightly different pink/purple colour to overcome most of the Purple Fringing I see from a couple of my lenses in certain conditions. It seems to work most of the time although experimenting to see which of the 5 'standard' variants are in play can take a few minutes. Red and blues (and the yellew green variety) are more problematic since they can appear as genuine colours, in their own right and a component of other shades, much more frequently that specific narrow bands of pink/purple. However the same approach might be worth considering. A dedicated tool of some sort would be great though. Many other applications seem to have added things that are useful for that sort of correction in recent times. Grant Perkins

tex
there was a kludge for this as I recall...

...using the tabs. Maybe Sebastien figured it out?

ysarex
I'll second that

I've spent the last ten days with LightZone and overall I'm pretty happy with it. What do I miss the most? CA correction.

Joe

todd
yup

yup

Catalana
I agree. CA correction can do

I agree. CA correction can do wonders for perceived sharpness on images shot with wide angle lenses (and other). I do have access to CA correction via other editors, but it would be nice to be able to maintain the workflow in one editor. :-)

hofnaar
we need it asap =)

we need it asap =)

RussellInCincinnati
CA, and purple fringing, correction would indeed be nice.

Would love an excuse to ditch lightroom and support LightZone. Unfortunately am hooked on easy, automatic lateral chromatic aberration correction, and easily applied and controlled purple and green fringing suppression in Lightroom 4.1 and higher.

/Russell

F9Race
+1

+1

Didn't find the thread, but as far as I recall it was planned to have a first PoC around spring time 2016. Any progress that could be reported, here?

F9Race

Photonoxx
The lens correction tool is

The lens correction tool is still in work I think, but for the moment, CA can pretty well be corrected with the kind of method described above

 

Personally, I use multiple Hue/Saturation tools with saturation 0 and vibrance 0 each with a predefined color selection which I adjust in function of tha photo I work on.

 

When applied I check in the maskview tab where the tools are applied and if there's more than thin lines where CA are present, I tweak the color range slider of the color selection tab to get thin lines which desaturate only the CA. Generally, I let the luminosity selection with no restriction, but it could be use for a more selective mask.

 

If you get thin line where CA are present but otther area where the mask is applied too, I just use region tool to limit to the proper area. Some of the tools are not needed in some photos and can just be removed from the tool stack

 

Here is a style I use regularly with the most common color fringe/CA I have to correct. Some tools are not used very often, but in some case they have some utility like "ultraviolet fringe" and "Red Cardinal fringe". After that, the color of the CA, I think, could be dependent of the lens/camera used, so it could (should ?) be adapted :

 

<Template version="8">
  <Scale Factor="0.2014652"/>
  <Image path=""/>
  <Controls>
    <GenericOperation Active="true" Collapsed="true" Locked="false" Mode="Normal" Name="Pink fringe" Opacity="100" OperationType="Hue/Saturation V3" layerControlsIndex="1" regionsInverted="false">
      <ColorSelection HueBlue="0.67058825" HueEnabled="true" HueGreen="0.1882353" HueRadius="0.86" HueRed="0.5137255" Inverted="false" LuminosityEnabled="true" LuminosityLower="0.0" LuminosityLowerFeather="0.0" LuminosityUpper="1.0" LuminosityUpperFeather="0.0"/>
      <Slider Hue="0.0" Luminosity="0.0" Saturation="-100.0" Vibrance="-100.0"/>
      <Checkbox/>
      <Choice/>
    </GenericOperation>
    <GenericOperation Active="true" Collapsed="true" Locked="false" Mode="Normal" Name="Cardinal Red fringe" Opacity="100" OperationType="Hue/Saturation V3" layerControlsIndex="1" regionsInverted="false">
      <ColorSelection HueBlue="0.03137255" HueEnabled="true" HueGreen="0.023529412" HueRadius="0.57" HueRed="0.11372549" Inverted="false" LuminosityEnabled="true" LuminosityLower="0.0" LuminosityLowerFeather="0.0" LuminosityUpper="1.0" LuminosityUpperFeather="0.0"/>
      <Slider Hue="0.0" Luminosity="0.0" Saturation="-100.0" Vibrance="-100.0"/>
      <Checkbox/>
      <Choice/>
    </GenericOperation>
    <GenericOperation Active="true" Collapsed="true" Locked="false" Mode="Normal" Name="UltraViolet fringe" Opacity="100" OperationType="Hue/Saturation V3" layerControlsIndex="1" regionsInverted="false">
      <ColorSelection HueBlue="0.12156863" HueEnabled="true" HueGreen="0.02745098" HueRadius="0.41" HueRed="0.050980393" Inverted="false" LuminosityEnabled="true" LuminosityLower="0.0" LuminosityLowerFeather="0.0" LuminosityUpper="1.0" LuminosityUpperFeather="0.0"/>
      <Slider Hue="0.0" Luminosity="0.0" Saturation="-100.0" Vibrance="-100.0"/>
      <Checkbox/>
      <Choice/>
    </GenericOperation>
    <GenericOperation Active="true" Collapsed="true" Locked="false" Mode="Normal" Name="Cyan fringe" Opacity="100" OperationType="Hue/Saturation V3" layerControlsIndex="1" regionsInverted="false">
      <ColorSelection HueBlue="0.7254902" HueEnabled="true" HueGreen="0.57254905" HueRadius="0.65" HueRed="0.25882354" Inverted="false" LuminosityEnabled="true" LuminosityLower="0.0" LuminosityLowerFeather="0.0" LuminosityUpper="1.0" LuminosityUpperFeather="0.0"/>
      <Slider Hue="0.0" Luminosity="0.0" Saturation="-100.0" Vibrance="-100.0"/>
      <Checkbox/>
      <Choice/>
    </GenericOperation>
    <GenericOperation Active="true" Collapsed="true" Locked="false" Mode="Normal" Name="Green fringe" Opacity="100" OperationType="Hue/Saturation V3" layerControlsIndex="1" regionsInverted="false">
      <ColorSelection HueBlue="0.08627451" HueEnabled="true" HueGreen="0.21568628" HueRadius="0.36" HueRed="0.09411765" Inverted="false" LuminosityEnabled="false" LuminosityLower="0.746" LuminosityLowerFeather="0.101" LuminosityUpper="0.996" LuminosityUpperFeather="0.0"/>
      <Slider Hue="0.0" Luminosity="0.0" Saturation="-100.0" Vibrance="-100.0"/>
      <Checkbox/>
      <Choice/>
    </GenericOperation>
    <Region/>
    <Region/>
    <Region/>
    <Region/>
    <Region/>
  <Crop Angle="0.0"/>
  </Controls>
</Template>

F9Race
Manual vs. automatic CA correction

Thanks a lot, I'll definitely try that out, when I have a little more time. Actually I had read one of your previous posts where you explained how to to CA correction manually, and I can confirm that your method works and that good results can be achieved with it. However, compared to Canon DPP, Digikam and Darktable it takes considerably more processing steps in LZ to get comparable results. I'll yet have to try the style you provide for that --- much appreciated that you share it with us!

If only CA correction wouldn't be such a tedious task with LZ...  ;)

But thanks again!

F9Race

 

F9Race

 

Photonoxx
You're welcome.

You're welcome.

 

It's clear that other software can manage "classic" CA with less steps, in the other hand, the LZ possibilities makes it able to achieve that without a dedicaced tool and additionally, LZ can manage other chromatic matter like halo or flare easier than some software like Lightroom. (in some case, it's just impossible or very difficult to do with LR in fact).

F9Race
Thanks again, Photonoxx!

I fully agree with you that LZ has many strenghts compared to other RAW converters. As an occasional user of such tools I find it LZ's UI a lot more intuitive than many other tools. I am still exploring all the tools and functions, and have only tried a small fraction of them, but the most important things can be done exceptionally quickly and with excellent results in LZ. I have learned to appreciate the overally approach and now find working with zones much more intuitive than working with layers.

The only thing that I really miss is a dedicated tool for CA/purple fringe correction. As I said, your style is a great workaround for the time being. But, as you write yourself, with some colours it's more difficult to apply than the CA correction functions in other software, such as Canon's DPP.

Of course, I could use DPP for CA correction and LZ for all the rest. However, that way I'd end up with a rather inefficient workflow and I would need a Windows machine for RAW processing, although LZ runs fine on Linux, which I much prefer.

So thanks a lot again for sharing your solution and your style! Howeber, I still hope for a dedicated CA correction tool in a future version of LZ. However, your style is a good workaround and certainly helps to bridge the time until then.

Jacal
Thanks, Photonoxx,

I have tried your template on two quite problematic photos, and it gives a very useful starting point. With more time invested in adjustments, results can be easily improved.

Photonoxx
Happy it can be usefull

Happy it can be usefull

Peter_M
+1

Just an +1 to the wish of a CA correction in LZ