Lost in Raw, exit from LR , moving to OpenSource but need strong advice

Hi there,

I want to leave LR, storing all my RAW in DNG.
All my metadata are stored in DNG or XMP.

In general, the only thing i modify on my photography in LR is

  • White Balance
  • and Color Temperature / Tint

Initial Dng after import in LR :

Temp 5500K
Tint +4

After Correction :

Temp 6800
Tint + 9
Exp +0,68

I test both import/view of my initial DNG with RawTherapy and Darktable, and the result is … different …

RawTherapy give better result, i suppose by reading some of the DNG metadata, but Tag of LR are not imported and white/color are not totally equals …

DarkTable result is strange, varying on photography (greenish, bland, teintless) due to the difference of White Balance / color management between the two software.

I see on forum that DarkTable/RawTherapy are more accurate on WB/Colors than LR, so my question are :

  • do you think there is a way to automatically adjust the White Balance / Colors of my thousands LR DNG photo during import into Darktable/RawTherapy ?
  • do you think i need to export to max JPEG (do you have a better format to propose ? Jpeg2000 ) of all my current phototography with LR preset, then restart from scratch for the next photo i take, in Darktable ?

Initial DNG :
IMG_1107.dng (20.5 MB)

Thanks for you time,

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In my opninion that background is fairly neutral grey. With the colour picker it says: 114 114 113 (RGB)
So using that as the reference point in the white balance module I get this result:
I also upped the exposure a bit to 1.2 EV

IMG_1107.dng.xmp (5.6 KB)

Yes, in RawTherapee as a starting point you have to create a Dynamic Profile rule, in your image you were not working with the Auto Matched High ISO profile which gets pretty darn close to the LR corrections you applied.

To just load the profile, Load the image, top right is Processing Profiles with a drop down box (Last Saved) and you select Bundled Profiles -> Auto-Matched Curve High Iso then a colour balance of 6800K and no tint, Exp +0.68 gets to the RAW below.


IMG_1107.jpg.out.pp3 (11.2 KB)

The information of setting up processing profiles so that you load a profile based on lens, film speed and camera is here:

https://rawpedia.rawtherapee.com/Dynamic_processing_profiles

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You know LR does all kinds of mostly subtle corrections that you have not influence on. It does not show you the real raw. DT does. RT does apply the auto-matched curve - it tries to match the embedded jpeg. I think you should use RT or ART.

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Darktable. Just use Spot on the white balance and move the exposure. Use scene-referred mode (filmic instead of base curve).


IMG_1107.dng.xmp (6.3 KB)

Edit: Set the white temperature to camera neutral and exposure automatic:
IMG_1107.dng.xmp (5.4 KB)


Close enough?

Hi @reyman and welcome!

I cannot grasp from your description whether you would like to

  • automatically find the correct white balance, or
  • adjust the white balance to a certain setting

Using Linux there are very many options available to you.

Have fun!
Claes in Lund, Sweden

First, thanks all for your quick responses !

@ Dinobe
You’re right, the image is already acceptable with few modification.
The wall is white for information.
This is highly subjective, but i prefer a little more colours/temp :slight_smile:

@ nodal
Thanks, very interresting to see that creating and applying “profile” close is possible during import. In this case, where the modification on image are stored ? RT overwrite values of LR directly in the DNG ?

@ betazoid
Ok, that’s interesting to see that RT try to match jpeg into DNG ! Thanks !
What is ART ?

@ Celsus
Thanks for this two possibilities. In the first mode, that’s funny because this operation is pretty similar to what i already do in LR when i modify WB and Tint with “pipet” :slight_smile: ! As i understand, these operations are manual, is it possible to apply in batch mode during import to get some close enough results for all photographies ?

@ Claes
Thanks ! I’m using windows at home and linux at home/works, best of two worlds :slight_smile:
Perhaps my objective is not clear, sorry for my english.

I want to apply process during import in DT or RT to get close enough result to LR actual DNG/JPEG. I would like to avoid readujsting thousand of photo in DT or RT if possible :slight_smile:

@All
Do you know into RT how to recover TAG from LR ? Is it possible ?

https://bitbucket.org/agriggio/art/wiki/Home

What I wanted to say earlier: LR does not only change the white balance, it does many other things without you being able to switch them on or off. You think you only modified the white balance but in fact I think LR does something similar as the auto-matched curve in RT. The real raw is usually VERY ugly and LR does not let you see it. The difference is that you can switch off the auto-m-curve in RT easily.

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RT will not overwrite any values, it stores them in a PP3 file that is saved next to the image being edited. This is called a sidecar file but you can use the processing profiles to do a batch conversion of your thousands of images.

But that is a choice, you do not have to process your existing images, you can just open them up in GIMP without touching anything, you can even open them up in RT or darktable and tweak them and even after you export an image because both RT and DT save the image adjustments in a separate file, you still have your original DNG that can be opened up in an editor.

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All the correction should be contained within the DNG file as per Adobe open format specification, whether that’s reality is of course a different thing when for example the data is matched to dcp profiles stored within lightroom. Attached is the DNG data extracted using exiv2 as a text file :slight_smile: there’s been some default sharpening carried out and colour noise removal, much like when the auto-match iso profile is applied in RT.

Some defringing too - which also would be a propriety Adobe information for the particular lens and how it’s applied, for example DefringePurpleHueLo=“30” is that a lot? it might be a lot on a slider that goes up to 50 but how is it mathematically applied to the image, is it only along edge boundaries? Who knows? which is why even when fully readable and an “open” format it doesn’t mean much except to point to general areas of image adjustment and doesn’t mean a translation to a DT amp file or RT pp3 file is possible.

IMG_1107.xmp.txt (7.9 KB)

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in all honesty it hardly seems worth shooting RAW if this is the case.

I have a fairly long in the tooth Nikon D700, and a much more recent X-T3 and both have near-infallible auto-white balance settings, and in the film days you essentially had one of two white balances baked in and its quite easy to shoot in that fashion digitally today.

this is not to discourage you from RAW processing, more a suggestion that if you’re going to go to the trouble I would highly recommend digging a little deeper into the tools we have available to unlock the full potential.

4 Likes

No matter which tool you pick, the community will be here to support you.
For darktable, here are the basic steps you can follow:


(Note: it was created using v3.0; with 3.2, things are a bit different, e.g. the grey-point selection slider is normally disabled: it’s recommended to first make sure midtones are properly exposed (exposure slider), and then adjust black and white points in filmic).

There’s a follow-up with a much more difficult photo (darktable 3.0 for dummies: hardcore edition), but you can wait with that one.

Most developers (at least on the darktable mailing lists) will discourage the use of DNG (unless that’s your camera’s native format, or your camera is unsupported).

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darktable 3.2.1
IMG_1107.dng.xmp (10,4 Ko) IMG_1107

2 Likes

Unfortunately, I don’t know how to make the white balance present “camera present” as Style, without having it copying the exact values, instead of computing it for each photo (maybe a question for https://discuss.pixls.us/c/software/darktable/19 ? ).
For the exposure module, you could make it automatic with a tendency to the right, like this:
00 Test_IMG1107_1.dtstyle (1.8 KB)
As anything automatic it will not fit every photo.

If you find the JPEGS already OK, take a look a this thread: Why aren't we utilizing embedded previews more in Darktable? - Some RAWs (at least from Canon - including yours) seem to already embed the full resolution Camera JPEG. A program like ERawP can easily extract the JPEGs from the RAWs. You could after only work on the RAWs that don’t quite satisfy you or are special to you.

Can you describe what you want to do? By default, darktable takes the camera’s white balance automatically, you don’t need to do anything.

Exactly, but if one changes the camera default to one the presents:
image

the present will change the values according to the image one is editing. But if we save the same white balance module on a style, it will apply exactly the white balance values

image

and will not use the present used before to the new image. I suppose for most situations this is the best behaviour, but if one wants the present “cloudly” to apply automatic to different images with a Style, it doesn’t work.

‘camera neutral’ is always 6502 K with tint = 1.000. ‘camera’ means ‘as shot’, using the WB the camera chose, and that will vary from image to image.

camera neutral Essentially sets temperature to 6502K. The actual math: it computes such white balance channel multipliers, so that pure white color in camera colorspace is converted into pure white color in sRGB D65. (pure white color here means having the same equal value for each channel = 1.0)

The other presets are also fixed (for a given camera; they vary by camera, e.g. the ‘daylight’ values for my Lumix LX7 [multipliers: 1.8906, 1, 1.7698] will be different from those used for Nikon D7000’s identical setting [multipliers: 2.02734375, 1, 1.390625]). The multipliers are hard-coded, and can be found in this file: https://github.com/darktable-org/darktable/blob/master/src/external/wb_presets.c

Wow Wow, thanks you so much :love_letter: for all this advices,
i need to take some hours to make some test. I try to do that before the end of 2021, and i post my feedback here.

Well, that will give us a lot of time :wink:

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You are right, the values are fixed for a camera. That also means we cannot apply a WB preset saved on a Style to a different camera ( which was what I tried…) because the settings are saved as “custom”. Thank you for your answer.