RT Would someone be so nice to explain to a stupid (me) a couple of things (retinex/dehaze)

@graypixel

Effort is not a problem. :slight_smile:

What is problematic is pedagogy, because each image is different, and the tastes of each are different. One will prefer a natural image - one that the photographer has seen - another prefer an artificial image with reinforced chroma, accented contrasts, visible perspectives.
For all agorithms that are not “natural” (Retinex, Tone-mapping, and some parts of Wavelet), this problem will arise.
I will add to Rawpedia, at the end of the current sections Retinex, a summary of recommendations and an “average” frame.

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I have add, in Rawpedia, a “tutorial” for a Haze Image
http://rawpedia.rawtherapee.com/Retinex/fr#Un_exemple_possible_-Dehaze-_quelques_recommandations

The goal is not to do a “good image”, but to explain how to use Retinex…and Wavelet in this case :slight_smile:
Jacques

Good summary.

Jdc
yeah! really really really well done! :smiley: u have to think about doing this for everything,:joy:
is clear short and detailed exactly what needed…
from that example start to dig into this tool and re-read the section up of the example understanding the technical explanation is much more easy.

i’m playing a bit following the steps, then i would try to move them to my photos, as fast as i get a decent result for me i would post it, (too many things too few time…sigh).

Thanks to all, Afre HIRAM shreedhar Morgan_Hardwood james agriggio and off course to you Jdc, for the patience the kindness and this come out a really nice thread.

Thank you, I’m glad that this help satisfies you.
I have just made a few minor changes to “Rawpedia”, essentially syntax
:slight_smile:

This is my try at the image:
Uploading…
I did a little of everything, noise reduction, white balance, vibrance, retinex, contrast, lightness, dark level, exposition compensation, saturation, light compression, shadow compression.
_DSC4138.jpg.out.pp3 (9.8 KB)

I added the color component to “Retinex at the beginning of the process” (with the same principle as in Retinex in Wavelet and with a slider “chroma”).

For this you must use the branch “newwaveletgtk3”.

The “Chroma” slider acts as a percentage of “strength” (luminance component).

Attention, the processing times are doubled (if the chroma slider is> 0) and the memory requirements are increased.
:slight_smile:

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