In very ‘oversimplicated easy mode talk’, highlight reconstruction tries to fix clipping issues directly after the white balance module.
So ‘it tries to make it look good at that point in the pipeline’. And if it’s set to ‘as shot’, ‘daylight’ or ‘reference’ or whatever… it doesn’t matter, it just has to look OK at that point :).
CC and the input profile works on that output.
In case of the CR2 file in the topic-start, there is very little difference between ‘as shot’ and ‘reference’, so this really doesn’t affect much. At least here on my system.
This shot has a bit of an issue where the reconstructed areas don’t match with the colors of the clouds around. So even if I get rid of the magenta of the clipping by reconstruction, it still has a cast compared to the white pure clouds around. Makes me actually kind of prefer the Lch-reconstruct which I normally do not like at all.
reconstruct-color and segmentation both add a color which shouldn’t be there IMHO .
Anyway, in the end you’ll end up with the same as always: Modern filmic tries to preserve as much color in highlights as possible. Because v5 got criticized of unsaturating the skies, I think.
So it tries it best to preserve all the color that’s there. In case of clipped highlights, there probably is some ‘false’ color in there that you do not want at all (like in this shot). With no filmic / sigmoid, just ‘white balance’, ‘reconstruct’ and put the exposure way down, so we can see what’s happening, shows this:
And filmic v6 tries to preserve that redish color in the reconstructed clouds, which makes it stand out against the more white clouds around it.
You can lower the saturation of the highlights with color-balance-rgb, or even try some masking there… or take a filmic approach which does not try to preserve color as much, which is perfectly fine in this case I think.
Preserve-chrominance mode to ‘no’, or ‘luminanceY’ often does the job, although with ‘no’ I often struggle to get the colors in the rest of the picture how I like them.
Filmic’s own reconstruction actually works quite OK here too. We do not want it to preserve the false color, so the slider in the reconstruction tab between ‘gray’ and ‘colorful details’ I move all the way to ‘gray’. And then I start lowering the threshold. You’ll often see that ‘just below 0 EV’ is all that’s needed, with a proper white-point set up. You can even move the ‘structure / texture’ slider all the way to texture, to get some definition back in the blown-out clouds.
I often test this kind of stuff with a very strong local-contrast enabled, just to make all the changes / details really visible (and turn off the effect or lower it later). My usual: local contrast ‘bilateral mode’ with the contrast set to 3, and then the detail slider way up.
Having the exposure at (my) default of 0.7 (With the reconstruction still enabled on segmentation). I enable filmic with (my / Aurélien) defaults: latitude 0.1, hard curves, maxrgb mode, contrast to 1.0. The only thing I then do is use the ‘auto white’ picker, and leave the rest alone.
With the local-contrast boost enabled to visualize things, you’ll see the issue with ‘maxrgb’ mode that you are having: trying to preserve the false/wrong color:
Now, just setting filmic to ‘luminanceY’ mode already improves it a lot:
You’ll still see some dirty color around the details, but it’s way less.
But to demonstrate, go back to maxrgb, and then set filmic’s reconstruction how I explained it (around -0.15ev, complete ‘texture’, complete ‘gray’):
All the dirty color is now gone, even in maxrgb mode. And we still have some cloud-definition in the clipped area. I see no difference with ‘reconstruct color’ and ‘segmentation based’ as HLR options with these settings dialed in. Lch maybe could’ve worked as well, but you need to tweak filmic white point some more.
But, instead of using filmic’s reconstruction on top, you also could add a color-balance-rgb instance, where you use the Jz channel (scene-referred luma as I see it, might be the wrong terms, but it explains it…) to mask out the ‘reconstructed highlights’, and then lower the saturation of it all the way. I guess that only works in this image, because the surroundings are also unsaturated white clouds.
mask:
result:
In all of these tests, using white-balance set to reference and then CC set to as shot, makes absolutely no difference to just white-balance set to as shot. So I don’t see the difference that is reported here between modern-WB and legacy-WB?
For an image as this, using filmic v5 is probably the easiest, but also a very logical way. Whenever I see someone saying ‘ok, I will change to preserve-chrominance no mode by default’ or ‘switch to filmic v5 by default’, I always want to explain what the differences are. Because otherwise it’s just waiting for questions again like ‘Filmic renders this desaturated’ or ‘all my color is gone’.
Explaining the differences makes it easier for people to directly target an option and change it, instead of just ‘trying out all the options to see what works’.
With or without reconstruction, you’re dealing with wrong color in the reconstructed area (in this picture at least). Filmic v5 doesn’t preserve color in the (extreme) highlights, so the problem goes away. But that might not always be the best way forward, specially if you do want to preserve color in the reconstructed area.
The modern-white balance method doesn’t seem to be related to this at all, it’s just another case of ‘clipped highlights and how to deal with them’, in combination with a file that opens with the wrong white-level set.
AFAIK, lch-reconstruction ‘just’ removes the chroma from the reconstructed areas. So the white-balance setting has absolutely no effect, because whatever the surrounding color is at that point in the pipeline, the reconstructed area will be completely desaturated.
The other reconstruction methods just try to ‘feel in the gaps’ in some way with the information around it that isn’t clipped. They don’t care if that information is ‘supposed’ to be blue, or magenta, or red, or whatever depending on your white balance settings… they just take the unclipped pixel-values and use them to overwrite the clipped channels. What the white-balance setting does shouldn’t matter, to be honest. Also, testing this (just having white-balance, reconstruction, and a massive lower-exposure setting to see the reconstructed highlights properly) and messing around with the white-balance setting doesn’t break the HLR module. Only when setting extreme white balance differences, but I’m guessing that I’m then seeing other issues as well.
so, in the end: I find it weird that so many people in this thread talk about a massive difference with legacy-WB and modern-WB. But I really don’t see it? What am I doing differently?
Yes, filmic options affect how the clipped highlights look, but changing white-balance around doesn’t seem to make it behave differently?