3D LUTs for Darktable

[rawnakc (rc)]

Where can I find some 3D LUTs for DT ?
I am kind of new to DT and feeling my way around all the modules

I assume the LUTs have to be specific for DT or can I use LUTs created for other photo applications ?

[darix]

https://docs.darktable.org/usermanual/development/en/module-reference/processing-modules/lut-3d/

[kofa (István Kovács)]

That doesn’t give much info, e.g.

While you can find hundreds of free LUTs on the internet, you should note that not all of them are compatible with the darktable environment and workflow – incompatible LUTs will not produce the advertised look.

@rawnakc : you can use the RawTherapee collection (search this forum, and you’ll find they are not intended to be precise, more to convey the ‘feel’), and I’ve also used some from On-1 LUTS from Download All Free ON1 LUTs - ON1. Then there are a few LUTs intending to reproduce the film simulations of Fujifilm cameras, but I have not updated this list for a looong time (I hardly ever use LUTs, in fact): darktable styles | Kofa's tech stuff

[darix]

Well if the documentation for darktable doesnt specify well enough what is supported and what not. may I suggest extending that documentation?

[kofa (István Kovács)]

Good question. It describes the module (what colour spaces and formats are supported) – and maybe that is the intention, not more. The whole darktable documentation is ‘spartan’ in a way (e.g. there are not many screenshots, that could go obsolete). That is probably no links are provided to sites with LUTs – and the original question was about those:

Where can I find some 3D LUTs for DT ?

What I meant with ‘not intended to be precise’ is:

How was the RawTherapee Film Simulation Collection created? And thanks!

I quite recently discovered the collection of Haldclut files for all kinds of film, available here (the link is found on the Rawpedia page ) and I am having a lot of fun trying them out (in darktable mostly) - some have lovely effects on colours which I’d never think of otherwise. I’m really curious how were these created. Did someone actually shoot film and digital versions on all these different film stocks, so they could be created with something like dt-chart? Or, maybe more likely, were t…

and

The source of film simulations

Portra 400 was likely a combination of multiple other efforts tweaked to something pleasing.

[priort (Todd Prior)]

https://freshluts.com/

[Bordwall]

I have a lot of LUTs I’ve collected from various “free LUT sources” online. By far the most used are:

• t3mujinpack - GitHub - t3mujin/t3mujinpack: Collection of film emulation presets for open-source RAW developer software Darktable.
• RawTherapee’s Collection - Film Simulation - RawPedia

One recommendation when using the LUT module is to use blending to adjust the opacity. You can also combine multiple LUTs to good effect. For example, I’ve recently started using a combination of “SoftWarming” and “Fuji Provia 100F” from the RT collection on my casual snapshots.

[kofa (István Kovács)]

The question is still: what do the LUTs require as input?
For LUTs, one needs input in 0…1 (0% … 100%, 0 … 255), because they can only map a restricted input range. But how does one get the data there? filmic and sigmoid, or tone equalizer all apply some curve, and the first two also explicitly manipulate the colours. If e.g. Fujifilm the LUTs were not created with the same preprocessing that you use, you cannot expect to match the Fuji in-camera processing (or that done using proprietary Fuji software). For actual film emulsions, even less is known, I think.

[priort (Todd Prior)]

There is that so on the rare occasion I use them I always use them after those modules but the thing I guess is they also expect a certain color space for the math to be "accurate and many of the Luts esp say the cinematic or log ones will expect one not provided as an option in the LUT module…I am often not certain with many of the luts what color space they expect unless it is provided in the name or description and so leaving the module on srgb takes the data as I understand it from the pipeline which might be in rec2020 to srgb to use with the lut and then it will output back to the working space I think??

[kofa (István Kovács)]

@priort

leaving the module on srgb takes the data as I understand it from the pipeline which might be in rec2020 to srgb to use with the lut and then it will output back to the working space

That’s how I also understand it.