Filmic RGB - loss of detail and saturation in high contrast scenes

How’s this look to you?

Not bad, it is certainly better than I could achieve. Thanks. How did you get that far?

But I am still seeing loss of detail in the brights. See circled and arrowed areas on your edit.

Without posting your settings its not easy to explain, why it doesn’t fit your expectations. Filmic is far away from beeing an automagic module. It just tries to bring the dynamic range detected by the sensor into the dynamic range of the output. It important for the module that you specify, how to do this …

Starting from where we are currently on my edit to get more detail back in those areas there’s several options, the whites a bit more to the right in filmic or darken highlights: gain/slope in colour balance, probably a bit of both I’d do. Could do it tone equalizer or a mask with a second instance in the exposure module.

My edit is just exposure to 1.00, flimic at 18.45 grey then adjusting whites and black, local contrast at default apart from highlights set to 0 to avoid any further clipping, contrast equalizer preset deblur: large 4, colour balance to get the saturation back I set output saturation to 119% and to brighten the midtones, denoise profiled default.

Default settings in filmic. Just activate the module and take it from there.

My question is how to adjust filmic to maintain the full dynamic range of the orignial picture for starters. This is just a random photo with high contrast and some good colours.

Ideally if I was processing this I would try to lift the darkest blacks slightly so that the penguins’ eyes were more visible and not touch the lights much. It seems to me that this is something that I should be able to do with filmic RGB but whatever I try I loose detail and saturation.

try OnetoRuleThemAll_OrNot.dtstyle (2.1 KB)
default settings in filmic are like a default haircut done by a robot - it might be ok, if your head matches. …

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Yes I know… If I knew how to do achieve a matching haircut I wouldn’t be in the barbers shop.

What I am asking is for some guidance on how to achieve something that is at least as good as the raw so that I have a start point to lift the black. So do you have any suggestions or are you just trolling my post? :slight_smile:

Yes I know I can use other tools, perhaps. But I would have thought that I should be able to at least achieve parity with filmic RGB and then tweak the blacks a bit.

To get the eyes more visible I’d use masks and the exposure module and then using the same mask other modules to sharpen, correct colour ect… flimic just to get a good starting point.

You can scroll down in the darktable manual, there is a basic workflow description. I saved that settings in a preset.
https://darktable.gitlab.io/doc/en/tone_group.html#filmic

have a look into my default style attached in my post - its build for a canon m6 and takes its exposure characteristics into account. Is that suggestions enough? Bu i can give further explanations:
1: do a basic exposure correction - if middle grey isnt set properly a default setting in filmic is unuseable, because it sets deviations for black and white to middle grey
2: find a setting for which black isn’t clipped and white isn’t clipped in the scene tab
3: tweak look setting but keep black and whites unclipped by limiting latitude if necessary
4: use color balance to fintune contrast and saturation
etc. pp.
dont expect filmic to do local contrast improvements because it just deals with global contrast

Thanks Nathan,

Perhaps I am not wasn’t very clear. I don’t care about the edit on this photo, it’s just one of thousands. I chose it to use as an example because it has pure blacks and whites (or damn near to it) with detail and colour in both areas. I am struggling because whenever I attempt to use filmic on a high contrast image I seem to end up with a worse result than when I started.

I am currently re-watching Pierre’s Filmic RGB: remap any dynamic range in darktable 3.0 video. but obviously missing something. :slight_smile:

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Thanks… I’ll have another read and work through it.

Thanks. playing the the default style is interesting. Out of the box it produces quite a useful result but in this case with the darks too dark and the oranges a bit over saturated. Could be the camera settings and such. I use a Sony a6500 these days but have photos from a variety of cameras that I need to set up styles and defaults for.

I guess I need to look at the order of operations in DT too. because it I turn off your settings for contrast equaliser, colour balance, and local contrast (just leaving filmic RGB) I am more or less at the best that I could do with just filmic RGB too.

Cheers and thanks
Chris

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Maintain full dynamic range is not possible, it’s not displayable on current output devices. Filmic applies curve that protects midtones and compress the high and low parts of the DR.

OK… I mean maintain the full range of the image ‘as’ displayed. See original post for example screenshot.

You don’t have to use filmic, if you want to keep the image as displayed.

Yes I know… but I see a use for it and think it should help in these cases…

You can see this video from filmic developer where the compression is explained

In any case in high dr image you will have to do a compromise.
There are some trics which may help to recover some part afterwards, e.g. idea from Boris Hajdukovic

Here’s a take using Pierre’s Filmic-based style along with an exposure and black level adjustment. To get more details in the highlights, I applied an rgb curve, applied after filmic, to increase contrast in the birds’ breasts.


2008-11-04 at 11-52-26.CR2.xmp (7.2 KB)

The XMP is from the current Git master (commit 9fc00e3f), so may not be usable in your version. So here’s a screenshot of the rgb curve settings and placement.
image

Your dilemma is one of the reasons I’m not too enamored with regard to attempts to abstract the filmic curve. Most tone modifiers can to an extent be described with a curve graph, which IMHO is the only intuitive way to assess the impact of a tone operator.

This screenshot is not darktable, but it shows a filmic class curve modified to address your specific image, along with a curve plot of the actual transfer function:

This filmic operator is the original equation laid out by Duiker, controlled with the coefficients A, B, C, and D. These coefficients have decidedly non-intuitive effect on the curve; suffice to say what I’ve dialed in is substantially different from the defaults, in order to flatten the log-style shape while retaining that little “ski-ramp” shape of the toe. You can see this easily in the curve plot in the lower left.

Thing is, you can do the same thing with a regular control-point curve. The point is, the filmic curve is designed to lift image values while preserving a film-like crush of the lowest tones. That lift is apparently not friendly to penguin chests. It took a rather aggressive modification of the defaults to address the need for retaining tonality in the highest parts of the data.

I’m not dissing darktable’s filmic, it’s a very powerful and appropriate tool for tone manipulation. I just want to point out that the curve it inflicts is an insightful thing to consider regarding the tool’s effect.

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