RawTherapee Chromatic Aberration


#1

Hey.
I have a problem with aberration correction. Automatic correction button is inactive.
How to deal with this. (RT 5.3) ??
Camera found (a6000). A lens selected from the list (Sigma 30 f1.4 DC DN)

Hubert


(Morgan Hardwood) #2

Hi @hubertus75
If you are referring to the Profile Lens Correction tool’s chromatic aberration correction checkbox, it requires that the lens data has chromatic aberration correction parameters - not all do.
http://rawpedia.rawtherapee.com/Lens/Geometry#Profiled_Lens_Correction
http://rawpedia.rawtherapee.com/Chromatic_Aberration


#3

What a pity…
Thank you.


(Morgan Hardwood) #4

It’s not a pity, it’s open-source, and that means that you can improve the situation:
http://lensfun.sourceforge.net/calibration/


(nosle) #5

@hubertus75 use the raw tab chromatic aberration fix instead. It works quite well in most cases. Just tick the box marked in red below.

2018-02-27-222613_414x877_scrot


#6

Thank you.


#7

Thanks o lot.


#8

There is also the filter “defringe” in the details-tab (I think it works better than the chormatic aberration filter). I am going to post a tutorial on my blog later this day, not sure in which language though


(Morgan Hardwood) #9

Each tool is best suited to deal with a distinct problem. It would be bad advice to recommend using one to tackle the other’s problems - as an abnormal case yes, but not as a general recommendation.


#10

Each tool is best suited to deal with a distinct problem. It would be bad advice to recommend using one to tackle the other’s problems - as an abnormal case yes, but not as a general recommendation.

OK. I expressed myself incorrectly. I meant: I would first check chromatic aberrations in the raw tab and then, if there is still ca, I would go to details - defringe.


(Morgan Hardwood) #11

Much better :+1:


#12

Hi.
I am waiting for your tutorial about it.

Hubert


#13

http://betazoid.bplaced.net/lilac/wp-content/uploads/2018/03/rt5.pdf

I chose German for the German Rawpedia is very incomplete.
Basically it is easy: Go to “Details - Defringe”, click on “curve: hue” and pull up the point at the basis of the color of your CA. Just a little bit is usually enough.


#14

Thanks! I will use your hints when I have a problem with the CA.


#15

It works very well! Thanks.


#16

how does the manual correction in raw tab work? is it pre-demosaicing?


(Ingo Weyrich) #17

Yes, but the manual settings are applied to the whole raw data, whereas the automatic settings are calculated (and applied) for tiles of the raw data.


#18

So manual settings should not create those zigzag lines sometimes seen in noisy images with auto correction enabled?


(Ingo Weyrich) #19

Can you provide an example please?


#20

I’ll have to some digging. But noisy images seemed to be the most susceptible to the visible tile lines, as well as images with large swaths of solid colour (blue sky).