Hi Mateusz
I would like to learn your step by step method of getting the LUT from SpektraFilm. Could you share the step by step details of it?
Thank you in advance!
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Hey I’m kinda of a noob when it comes to installing things via terminal, if it won’t take too much of your time could you create a little video demonstrating the process in conda?
Hi everyone!
Is anyone dealing with a decrease in saturation when exporting? These are both screenshots for the sake of storage here, but I think it’s visible. The top one is the image in spektrafilm, the bottom one is the export. My output/saving color space are both sRGB.
Be sure you try to evaluate the image with the hqp enabled…ie the high quality preview and then when you export set hqr …reprocessing to yes… This should make for a good match and finally maybe check what your display profile is set at and using…That is the profile that controls how your preview looks on the monitor…
Theres been a persistent colorspace embedding issue on my end, maybe you share the same. Just assign a sRGB colorspace and the colors should pop back.
Sorry, where would you enable hqp? I only have a “Preview” option. When it comes to exporting, once I click “Save” that’s it, there are no reprocessing to choose or other exporting options. Weird.
As far as other settings, my input color space is set to ProPhoto RGB and output/saving color space is sRGB. I have tried this with “Scan for print” enabled and disabled but it happens anyway.
I’m on my phone and can’t do a screen shot. It’s in the lower ribbon bar hover over the icons…I think it’s next to Raw overexposure. It uses full image data so it’s the most accurate but also slower…
I can’t find that option. It’s as if I have a different version of the app, but I’m sure it’s the most recent one.
This is about spektrafilm, not darktable. I don’t think there is a high quality option in spektrafilm.
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This would explain the confusion, although my problem doesn’t have to do with image quality, but with color shifts in the exported file. Doesn’t seem like the majority are dealing with this so I wonder what am I doing wrong.
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i think it is a problem of display profile and monitor calibration. napari that currently run the image viewer in the simple spektrafilm gui is not color managed. so it is a bit hacky.
are you on windows? if yes, have you tried to click and unclick the button “use display transform” under the CONFIG tab? if the display transform is retrieved it will be signaled in the status bar. that works only in windows unfortunately for now.
without display transform you rely on the “output color space” in the MAIN tab, by setting it to something that somehow matches your display calibration. maybe you have an sRGB profile or settings in your os? in that case sRGB output might improve the situation.
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What is your monitor color space? If it is wider than sRGB, the image will appear oversaturated if you set the output color space to sRGB.
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Ya sorry I thought dark table was in the workflow…
Now I get it! I’m using a Mac and the screen gamut is Display P3, which is wider than sRGB. I wasn’t familiar with napari, but if it’s not color managed then it’s explained. Fingers crossed for a ICC-aware display management in the works.
Anyway @arctic congratulations for what you’ve built here and for taking the time to help out.
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thanks! 
you should try to set the output color space to Display P3, if i remember well it was added long time ago exactly to have a better color reproduction on mac.
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Exactly, that‘s what I did on my iMac with DisplayP3 gamut.
Congratulations and big thanks for your great work!
16 bit TIFF is back
exr is 16 bit by default
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- Download or create Hald CLUT Identity.
Since I have ImageMagick, I created mine using a command:
“convert hald:12 -depth 16 -colorspace sRGB hald12_16bit.tif”
You can also download this one:
File:Hald CLUT Identity 12.png - RawPedia
2.Import Hald CLUT into spektrafilm - In the Input tab select input color space to srgb and check the “apply cctf decoding” ON
- In exposure tab I uncheck both auto exposure and auto compensation.
camera compensation ev is set to 0 and print exposure is set to 1 - Turn halation, grain, preflash and diffusion off
- I leave couplers on but it is important to set diffusion size um to 0
- In the scanner tab set unsharp mask and blur to 0
- Press scan and save as .png
- Using PNG2Cube program convert Hald CLUT file into .cube file. Program is very simple to use and instructions are
- Use these luts after converting your footage to rec709/gamma 2.4.
I created a “preset” with the exact settings I use for my luts:
You can use “load from file” in spektrafilm to apply the settings.
One thing I cannot grasp is the size of the .cube files generated by PNG2Cube. Each lut is over 50mb which should not happen! I suspect that resolution of Hald image is too big. Hovewer re-exporting the lut with Davinci Resolve as 65-point cube creates appropriate file size
It is a miracle that I have managed to make this work because I have no idea what I am doing with all of this most of the time!
It works nicely for now but I really hope that @arctic will implement dedicated lut export menu with options for print-only and film-only luts in the future!
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thanks a lot
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Thank you so much for the in depth guide Mateusz!!!
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