Problem here is, that other SW competitors cope with that pretty well and for example Darktable is able to remove the CA + purple fringing successfully just by applying default modules …
Help me out please and tell me, what I do wrong here … Here you can download original RAW file, lcp file for my lens and also my pp3 (I did a lot of experiments with it, this version is just with enabled module and not doing anything fancy … I believe that the purple cast is partly caused by default CA correction in Raw → Chromatic Aberration Correction → Auto-Correction enabled …)
I noticed two things when looking at your RAW+sidecar:
You seem to be using the auto-matched tone curve, which doesn’t do a good job and makes the fringing more noticeable.
Avoid colour shift is ticked in the RAW → Chromatic Aberration Correction section.
About the first point: Dialling this curve in yourself is the better way to do it. The results of the automated curve is based on the embedded jpg and can miss the mark.
About the second point: At times RT does actually colour shift when the Avoid … is turned on. This is one of those cases, so untick it.
a) What processing profile did you use as a base for your developing?
b) Check the histogram. Red channel is blown in the (output) color space you have picked.
Hello @Claes … I think that red channel blown is the known issue with Nikon cameras … I think it will be always blown no matter what profile you will use … You can download an original RAW above and check it for yourself but I don’t believe that it’s the matter of profile that the red channel is blown out …
Check the state of the gamut button.
Yours is off = histogram shows the gamma corrected output profile, i.e. sRGB.
Mine is on = histogram shows the working profile, i.e. ProPhoto.
oh, thanks so much … I see … but what is the difference please ?? o.O … I don’t see there any real difference after enabling that … ofc beyond the histogram change … Please if possible try to explain me that same like if you were explaining it to your mum (or granny)
I had great fun with it, even if it had a limited colour space,
not very many variations, and not any really intense colours at all.
I call it my sRGB box.
The graduation gift you gave me some years later was much more colourful!
It has more colours to play with, many of high intensity. That’s my aRGB box.
After that short intro, there is a book I think you would like:
Andrew Rodney’s Color Management for Photographers.
(You will find it on the Web). Study the illustrations, work through
the tutorials – and really enjoy yourself!
Different devices use different colour spaces. This simply means that they can represent (sense or display) different ranges of colour. When you take a photo, it is created in the camera’s native colour space. Then, it usually gets converted to your software’s working colour space (such as ProPhoto or Rec2020); when it leaves the editor, it gets converted to an output space (such as sRGB, Adobe RGB). Finally, it gets converted once more to the output device’s colour space (whether it is a printer or a display – note that is is also possible to convert from the working space to the output device’s space).
Some of those spaces are limited in the sense that all signal components (for example, R, G and B or C, M, Y, K) must be within 0 and 100% (0 and 1, 0 to 255 or 65535, and so on). Being negative or over 1 is not necessarily a problem during processing, that depends on the algorithms of the software being used.
Now, if at any point any signal is < 0 or > 1, and the device (or algorithm) cannot deal with that, the signal will be clipped (to 0 or 1). This leads to colour distortions; a famous example is signals clipped in camera, when, if only a single channel is clipped, white balance will be broken in highlights, usually manifesting in purple spots. Another example is sunsets, which can become ‘radioactive yellow’ when red tops out, but green and blue are not completely saturated and continue to increase when exposure is increased.
In your case, sRGB cannot represent the saturated red that ProPhoto can, and if that is handled by clipping, colour distortion will occur. That has nothing to do with the image coming from a Nikon camera.
Different software handle that transformation differently; darktable’s filmic module is infamous for creating salmon-like pink sunsets; brutal clipping can create that radioactive yellow; some methods involve desaturating and/or reducing the brightness. See, for example, here: sRGB gamut clipping
If the end result looks OK, then don’t worry too much about clipping. However, if colour look distorted, look for clipping and try to reduce/eliminate it.
