filmic, a personal view


(ph. weyland) #41

I agree !
The kind of image which seems to be difficult to treat with filmic, is when the details I want to get are in shadows and highlights more than in midtones. The S curve tends to compress them on both sides, giving the opposite effect.
In that case I think I should compress the midtones instead and get (or keep) contrast in shadows and highlights, what I did with tonecurve:
image


#42

It really depends on your learning and communication style.

The tone curve may be easier to grasp because it is more visual and direct than filmic, which is why I completely understood where @gadolf was coming from when he asked if we could adjust the curve of the filmic module directly.


(ph. weyland) #43

Agreed. And I think the tonecurve spline curve is probably not the best tool to mimic and control a real filmic curve with toe and shoulder …


(David Vincent-Jones) #44

I look upon images as being the sum of their numerous parts. Extracting, for me, the appropriate amount of shadow and highlight detail is critical in how I wish to see a final image. The mid-tones may dominate an image but the S&H are the icing on the cake.


(ph. weyland) #45

I can agree on this. Filmic works very well for me to extract shadows from dark along with midtones. I struggle to get good highlights (detail and especially saturation).
In fact unbreak works pretty well also to extract shadows (thanks to log curve). But the correction to be done on top of it (tonecurve or color balance) is usually severe. I’ve work a bit to build a sigmoidal curve as a second step in unbreak to decrease the afterwards correction (https://github.com/phweyland/darktable/tree/ub-sig). But that doesn’t help neither to get (to keep) both shadows and highlights.


(Aurélien Pierre) #46

That is a nasty one, but you need to decompose what’s going on : your scene is not HDR (I get about 8 EV of dyynamic range) because of the haze that diffuses light and wash your blacks. So, filmic will not be able to give you the contrast you expect all alone, you need the dehaze module too.

Filmic is not a creative module, it a sort of view-transform, trying to squeeze the dynamic range of the camera into the dynamic range of the destination medium (and uses the film behaviour as a reference). Its benefit is to keep the scene-referred ratios untouched during non-linear operations, that would normally destroy them (that is, with chroma preservation on), and let you deal with them manually (although that can be trecky sometimes)

It desaturates highlights and shadows outside of the latitude, so you can manage where it desaturates with the balance shadows/highlights, by sliding the latitude. In your reference image, I find the bright highlights have an unpleasant piss yellow, because the red is clipped, so the only solution to me is to let them degrade toward pure white.

What did they do in the darkroom ? Dodging and burning. You can always mask the highlights with a parametric blending and the mask feathering.

So here is what I get:

Not masking (filmic + dehaze + a bit of contrast in color balance + local contrast):

Same but masking highlights (this piss color is really disturbing):


#47

Here is may take on it with filmic, and a bit of color balance and local contrast.

Auswahl_083

It is a little darker than the other approaches, but I think I prefer it this way.


(Tobias) #48

@aurelienpierre
I like your first version without the masking better, because in the second the clouds moves attentions away from the town.


(Carmelo Dr Raw) #49

I’d have a question: am I allowed to post here a non-DT processing, which however uses yet another kind of filmic-like tone mapping? I’d like to show what can be achieved on the Cahuzeres image, for the sake of comparison…


(ph. weyland) #50

I’m not entitled to allow anything as i’m not moderator. But for the sake of knowledge improvement I would you do so …


(Carmelo Dr Raw) #51

Thanks for your answer! I’ll take two likes and one positive feedback as a good indication that I’m not hurting anyone by posting my edit here… so here it goes:

The code is not yet committed to github, however here is a preview of the applied tone-mapping curve and the corresponding parameters:

@phweyland the sky has much less contrast compared to your original edit, due to the highlights compression in the top portion of the curve… how does this match with the scene you have seen with your eyes?


#52

My take with exposure, filmic and color balance, no local contrast

20181109_Cahuzeres_221.NEF.xmp (11.3 KB)


#53

Something else without a filmic module.

20181109_Cahuzeres_221_01.NEF.xmp (11.9 KB)


(Andrew) #54

I don’t use DT, but I like this Filmic look and find it interesting. I’ve been trying to produce similar results with RT but can’t. Here’s a version of Cahuzeres but I can’t reproduce the charm of the foreground in @aurelienpierre 's versions above.


@aurelienpierre , is there a tone curve shape for use in “normal” tone curve tools as in RT which approximates to your Log process?

I’ve also tried with the woman in the street image and again I can’t get the clarity delivered by DT Filmic. For example the people under the “5” sign are just clearer and more nicely rendered with filmic. My effort -

I notice there are appreciable areas which were out of sRGB gamut and which were clipped into the jpeg. Is this common with filmic? Is that what film does, i.e. very saturated mid tones? (Mine is similarly clipped).


#55

Maybe you are not drinking enough?! :stuck_out_tongue_winking_eye:


#56

mh… maybe it should be a little brighter. Here is a second version

Auswahl_084


#57

Hi there,

here is my version.

  • exposure -1/3 EV (to avoid clipped highlights)

  • activate Filmic Standard

  • grab gray luminance somewhere on the church-tower (color picker => 2.6 %)

  • higher black relative exposure to gain some contrast (-5 EV)

  • higher latitude to “filmic” :smile: the midtones (4 EV)

  • preserve chrominance to punch up the colors

  • the rest is cosmetic stuff to desaturate the foreground, punch up the red in the sky a little, color denoising, sharpening and so on.

By the way: Thx to aurelienpierre for this wonderful module !

Greets
Jürgen

20181109_Cahuzeres_221_01.NEF.xmp (6.1 KB)


(ph. weyland) #58

It was a very warm after sunset sky over an autumn landscape. More or less the tones of my original edit.

@aurelienpierre
What you say makes sense and you get here more than I’ve got from this image (I love shadows and midtones of your first image). Indeed clipped highlights are disturbing.

This said, I wanted to illustrate that Log + S curve (filmic like) manage quite well shadows (one curve controls the other one) and midtones, but tend to sacrify the highlights (both curves compresses the highlights). The @Carmelo_DrRaw photoflow image seems to confirm this.

Saturation remains for me a difficulty, at least for this kind of image, to get more or less the right one both on shadows and higlights.

I share the need to desaturate the shadows but I may not want to desaturate the highlights…
Then balance shadows/highlights has another pupose (shaping the S curve) than managing saturation. Mixing the effects doesn’t turn the module easier to use. Independent saturation balance would make more sense to me.


(David Vincent-Jones) #59

Nice … but I prefer it with a small amount of haze-removal that allows a slightly better object definition.


(ph. weyland) #60

Some play here to mimic the S curve: https://www.geogebra.org/classic/k7tqyyuj.
For implementation arc portions are missing (geogebra draws them alone).
image