Struggling with White balance

Hi there,

I’m still fairly new to DT and have been really enjoying 3.6.

Recently I got my first new lens (the Panasonic 14-140) and have been playing around with it. However, I’ve started to notice that all my photos have a reddish hue to them when imported to the darkroom. I’m really struggling to use colour calibration to get a similar whitebalance to what the jpeg displays (which is usually right.)

Going back to some of my older unedited pics, they have the same issue. I don’t remember this being such a problem before (a few months ago). I wonder if I’ve changed a setting on my camera by accident?

The odd thing sometimes in a photoset dt seems to get the right wb first go. I have a feeling I’m not really using the color calibration module properly. I just use the color picker tool then try and fiddle until it looks about right. If there’s something definitely white in the picture I’ll use that to pick the whitebalance.

Here’s one that has given me particular issue. It’s not very well framed as my friends were moving too fast for me!

The clouds ended up tinted weirdly blue and the rest of the scene still has too much red in I think. The raw preview got the what the scene looked like pretty well, just needs some exposure adjustments and I would want to add a mask around my friends to bright them up a bit.

Here’s my go:

Here’s the raw preview (extracted with exiv2. I might start shooting raw+jpeg as often I struggle to get something like what the camera produces)

P1080027.RW2 (18.7 MB)

The pic is licenced under creative commons - so do as you please :slight_smile:

Any input will be much appreciated!

edit: forgot my xmp sorry:
P1080027.RW2.xmp (23.4 KB)

my attempt on the laptop ( in the direction of “warm tone”)

i am not a fan of the WB of the module “color calibration”.
it always looks “wrong” and “unnatural” to me.

the reddish part can be solved quite well with the module “color look up table”.

…translated by deepl…

Struggling with White balance_P1080027

Struggling with White balance_P1080027.RW2.xmp (12.7 KB)

Amazing! This is exactly what I’m after. Will study the xmp :slight_smile: thanks!

Did it look red when you opened it up? What were you first steps to correct the overall wb?

If I use the eye dropper in the color calibration module, it looks fine. Not sure why it doesn’t get it right out of the box, but its easily fixable.

Fixing with with the color lookup table is interesting advice.

Using my hack software, with the as-shot camera white balance I got this for linear RGB, no tone curve:

The “red” I see in the foreground looks to be the mix of dirt and grass, and otherwise the camera white balance looks okay to me. I added a rather pedestrian filmic curve to lighten things up, and now the mix of dirt and grass is evident:

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Looks similar to this https://github.com/darktable-org/darktable/issues/10111

Black points set to 139:


P1080027.RW2.xmp (12.0 KB)

Black points default:

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Can you post your result with the eye dropper? Did you do it over the whole picture? For me it still ends up tinted red on the path. Though the rest of the image looks more or less right. Maybe there are just more browns poking through than I thought

Currently there is an issue with black levels of Panasonic cameras, which causes a red/magenta tinge. Check if you can fix your images by raising the black levels by 15. See the issue linked above by @apostel338 , and also https://github.com/darktable-org/darktable/issues/10008.

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Ahhh life saver! That’s what my images used to look like when I imported them into DT. I guess I’ll just use this work around for the foreseeable. Do you think that if this issue gets fixed it will make my images look weird since the blacklevel will be increased?

If the fix isn’t simply, that 143 becomes the new default value for Panasonic cams, I think you would have to change back your edits. But you can easily do this with selecttive copy and pasting to all your images at once.

grafik

As @kofa mentioned, setting points to 143 seems better than 139.

There’s something funny going on there. In color calibration, if you choose for the illuminant “as shot in camera” (maybe more than once), then it will pick up the correct coefficients from the raw file. Not sure why it is not picking them up correctly first time…

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I’ve experienced something similar occasionally.

I have experienced the same. I have also filed an issue in github. Also I have experienced some random magenta casts when I open the image first time.

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Although unrelated to the GitHub report, I occasionally struggle with Color Calibration with my Canon CR2 files. I don’t get a red/magenta tinge, per se, but I find that the CC module tends to render my images towards the magenta side and then I have to create a new CC instance and use the mixer to bring things in-line. It can take a lot of time.

As always, I won’t rule out operator error, but sure would like to get my WB nailed more quickly.

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Just to update - all my old edits are fine they already have the raw black points set at 143. Seems to only affect new images. I guess 143 is the correct level always?

In the metadata for your image, there are three tags that specify a black level:

$ exiftool -G P1080027.RW2 |grep Black
[EXIF]          Black Level Red                 : 128
[EXIF]          Black Level Green               : 128
[EXIF]          Black Level Blue                : 128

However when I open your raw, libraw (the library I use to read raw files) reports a black level of 143. So does rawspeed, the raw library used by darktable…

Dave you don’t need a separate instance…just change the mode in CC to custom and use the chroma slider…dial in more correction by increasing or pull back by going to zero…usually the hue is not off from the global auto selection but you can tweak it too…if I am uncertain I often go this route…take chroma to zero so that I see what zero correction looks like and then bring it back…this is also a good way if you are trying to relight your image and just reduce or enhance the cast/lighting but not neutralize it…

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I wouldn’t be as negative as Suki, but I feel like getting more consistent results with the old colour workflow. At least with my Fujifilm, the white balance then corresponds more to the JPGs and is less reddish.

I’m having the same issue with my G7. How do you deal with it? Change all the black levels in raw black/white point to 143? My pictures not always show the same value (128, 128, 128, 128). Sometimes they are (128, 127, 127, 128) or any other combination) Do you change the black levels accordingly, or just straight to 143?

I just took @Jragon’s raw and evaluated the application of the camera-supplied value of 128 with 143. 143 looks like what I posted previously, 128 looks like this:

The camera’s value clearly doesn’t sufficiently mitigate the sensor’s dark current bias. So I’d say, use 143…