ART vs dt basic processing

Unless explicitly asked for a specific version I’m always on the latest master when doing edits for Pixls. The latest build from this morning tells me I’m on: 3.5.0-2204-g834120353 There have been a handful of merges since yesterday.

My edit uses the latest demosaic, filmic rgb (v5) and color balance rgb the first two have new option and/or are tweaked and the latter isn’t even part of 3.4.X.

I do believe that you would be able to replicate the ART version, but it will take much(?) more work even if you would have access to the latest updates/modules.

I’ve read the other replies and I do have to agree with age when it comes to filmic and how it handles, or mishandles, saturation/chrominance/gamut. This is why I often (have to) change the default preserve chrominance setting in filmic’s options tab and lower the middle tones saturation slider in the look tab.

That’s funny, I am on darktable 3.4.1 here, too (Archlinux).

Filmic for sure but @aadm had also added extra saturation with color balance, local contrast at 168% and I think he had cranked the filmic contrast up to 1.68 or something…the point of my post was that he was not comparing apples to apples as best you can so I went back and tried to do that with out any added edits and modules. I am in agreement with you there are a couple of filmic settings ie the midtone boost and the color preservation that can alter things colorwise for sure and as well DT expects some exposure tweaking at the outset.

Just tried: Your sidecars load fine on my 3.4.1 version (Debian).

It is worth noting that even with ART you can have a pretty wide array of starting points…so comparing here…first the default profile which enables the automatch curve, then using the DCP file from adobe, then finally the DCP but disable the additional automatch curve. You could also come up with additional versions if you turn off one of the 3 parameters that you can control in the DCP. So in the end the user just has to decide what looks best to them…

image

20210507_CRP0868_artdef

20210507_CRP0868_DCPAM

20210507_CRP0868_DCPNAM

Ya much as Tim says above I have a filmic preset I call neutral where I set it up as noted below in the manual and I also turn off the color preservation so that I can see how that looks at the start. Then I have a few others to cycle through that use default filmic settings and just change the preservation mode. While its nice to have the option to do so its a distraction trying to figure out what looks best :slight_smile:

Note: filmic rgb cannot be set with entirely neutral parameters (resulting in a “no-operation”) – as soon as the module is enabled, the image is always at least slightly affected. You can, however, come close to neutral with the following settings:

in the look tab, set contrast to 1.0, latitude to 99 percent and middle tones saturation to 0 percent,
in the options tab, set contrast in shadows and in highlights to soft.

In this configuration, filmic will only perform a logarithmic tone mapping between the bounds set in the scene tab.

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What is your histogram profile…looks like srgb??

My closest try on the second one with sigmoid and a bit of color zones.

dt 3.5.0 + sigmoid

20210507_CRP0916_03

20210507_CRP0916_02.dng.xmp (8.7 KB)

a minimal editing with only exposure and filmic based off on my previous edits
20210507_CRP0868.dng.xmp (11.0 KB) 20210507_CRP0868_02

20210507_CRP0916

You will notice that if you just set color preservation to no and the midtone boost to 0 and all else default the the default profile in ART and DT result are very similar again without the WB discrepancy shown by the OP . A key missing element also is lens correction. It is turned on in DT but the lens is not recognized so there is a strong vignette. If you manually add the EF 50mm 1.8 this also improves the image. The same appears to be true for ART.

ART default no Lens
20210507_CRP0916_artno lens

ART default with Lens
20210507_CRP0916_artwith lens

DT disable filmic color settings no Lens
20210507_CRP0916_dt_no lens correctted

DT disable filmic color settings with Lens
20210507_CRP0916_dtlens corrected

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My smartphone struggle to load the page, could you resize the images?

Please remember that we prefer HD quality for images that don’t need great detail. Multiple 16MB jpegs is completely over kill!

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I agree, looks very close.

Nevertheless, under the vectorscope you can spot some differences in colorbalancing:

ART
Clipboard01

dt (your setting)
Clipboard02

Especially hue & chroma of the blue and red don’t match.

Without seeming flippant, from past experience, I, have found trying to get the result of software x to match software y isn’t good for your long term mental health.
There seem to be nice outputs from both here.
I use both darktable and ART, and depending on the picture, I sometimes prefer the default starting point of either.
dt is slightly greener by default, so reducing the blue slider on the green channel tab very slightly can make skies a more pleasing slightly purple blue colour, which can help…

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Ya I wasn’t really looking at it on that level. Also I map from rec2020 to relative intent srgb and I think art is maybe Prophoto to srgb…to either relative or perceptual…I didn’t check. I was more so trying t demonstrate that a couple of small setting were mainly contributing to the users dramatic difference and pointing out at the same time that they had added several modules which were manipulating contrast and saturation in the DT examples. I did note that using as shot WB for both programs produced slightly different wb settings so that was interesting…Lots of nuance but again I was just trying to point out that the original setup for the comparison needed a bit of context….

Thanks for sharing…maybe I will try to look at working color spaces and rendering intents and see if it makes the exports a bit more similar wrt color content….

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Sorry I just exported them at 95% and never even noticed how big they were… those file sizes are crazy. I’ll replace them with lower res/size images when i get home…

Ah I didn’t know about the latitude setting, this makes a big difference. Does latitude at 99 negate the gamut mapping age mentioned? Certainly yields a lot more saturation. And it may be trivial, but why 99% rather than 100%?

I think the discussion on how to set up Filmic is interesting and useful. For example, I have been fiddling forever with the preserve chrominance setting because I simply thought that I had to choose one option, and that the “no” option was not acceptable. But instead many of you believe that saying no chrominance preservation is perfectly ok!

The thing is, I still didn’t know how to make the shot of the building a bit warmer. I went back to some of the discussions I have bookmarked and following @s7habo advice in this thread I have realized that a simple modification in the channel mixer does exactly what I was after!

This is the tiny thing to do (green channel, increase Blue and reduce Green):

2021-05-14_00-23

And these are the results:

BEFORE

20210507_CRP0868_02

AFTER

20210507_CRP0868_03

settings for the second photo above:

20210507_CRP0868.dng.xmp (17.2 KB)

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Channel mixer is a powerful tool…
.

Done…