I have an odd question. After I export JPG images from Darktable (4.6.0), they look very similar in OSX Finder and Google Photos. But they look different when I paste them into various social media – even if I paste them out of Google Photos.
Here, for example, is a frog. The light version is what I saw on my screen, in OSX, and in Google Photos. The dark version is what happens when I import that very same JPG file into Facebook, Discord, Reddit, or LinkedIn.
I am somewhat baffled – is there an internal setting I’m missing? My export settings are JPEG (8-bit); allow upscale & resampling; profile is currently linear Rec2020, but I saw this with both “image settings” and sRGB first, and intent is “image settings.” I don’t apply a further style at export.
The profiles supplied with DT don’t support rendering intents…they have no impact unless you use a profile that supports them …then DT will save the rendering intents… now exporting in linear rec2020 in a non color managed app would give that dark image…
By that I meant Darktable’s default or included profiles… I believe they are all of the matrix variety and as such they don’t have the necessary tables to do rendering… if you instead substitute for example one of the color.org profiles for say sRGB output then your selection for rendering will be apparent… with the default DT profile …it will always look the same…
There is a folder that you can create in the configuration folder called color. There are 2 subdirectories … in and out for input and output profiles…this is where you can add your own custom display profiles or printing profile etc of the icc variety for use in DT…
I went back and edited the post…Thx
I use the appearance and the preference versions … the later seems to have a larger difference between relative and perceptual rendering and the former is supposed to be a good profile choice when moving from colorspace to colorspace according to the description provided…
Thanks for the thoughts and feedback! I’m not sure I know which profiles from color.org to grab – the page is a little intimidating.
As I write this, I’m noticing that the copy-paste out of Google Photos produces a PNG. So perhaps the problem is in Google’s (etc) JPG → png conversion, interacting with an undersupported color table?
What is your output profile on the image? Rec 2020 is OK for a working profile, but output should normally be sRGB.
If, in the darkroom, you zoom in to 100%, or you enable the new full-resolution processing feature in the darkroom (only available from 4.8, you won’t find it in 4.6), does the image brightness change? Fine patterns sometimes cause such issues (the image is processed in a scaled-down version for performance reasons).
I updated the post wrt the profiles and a link. These profiles will allow you to export in the different rendering intents. I think your issue is still color management in the other apps and not rendering intent…
Even tho’ it’s a Matrix Profile it does have a curve. So, if some of your target apps actually apply linear then that would explain the occasional dark image … EXCEPT …
… you told us it also happens with sRGB! “Illogical, Keptin”, said Spock.
I’d put money on your “intent is image settings.” but have no idea what that means …
I assume that you have good reason to use that particular profile … perhaps you use a Rec.2020 monitor?
P.S. just noticed you said “copy/paste” - is that really how you view an image in an another app?
As for sRGB I wonder if his monitor being an Apple perhaps might not really be close to sRGB and so exporting to that and then not having that color managed might still look off… but that is only speculation…
I think if you try xnview or bring it back into DT and it looks okay then there is a color management issue in those other apps … and never the less if this is for social media exporting to rec2020 is not the way to go…
Some of it in the sRGB case could be the difference between a gray background for editing and maybe white on social media??
In any case if you check your export on a known color managed viewer or back in DT and its okay then for sure its an issue with those other apps I would think…
None of them. That’s unlikely to help anything. And @priort wasn’t suggesting that you should get anything from there. He was merely explaining some technical details that you don’t have to worry about.
You did not in fact share all relevant settings. You forgot the output color profile module. Here’s how it should be set:
Unless you have a specific reason and understand color management, you should always use sRGB for export. A larger gamut is not automatically better.
The image settings in the export module means that output color profile is used:
I’m confused by your use of the term “copy-paste”. Do you mean that you actually copy the part of your monitor that shows the image and then paste that elsewhere? Or are you conflating it with save/export/download/upload/etc?
Google Photos on the web doesn’t let you download a JPEG as anything other than a JPEG, so if you get a PNG, you’re doing something else. If you do a screenshot (copy), then the format is determined by your operating system or screen capture program, not the program showing the image.
So I think I understand what you are doing, and - well - don’t do that.
This is what I think you’re doing:
I suspect that you’re right-clicking the image in Google Photos and selecting Copy Image. I’ll have to do some testing to figure out what exactly you’re getting, but it’s not the original image, that’s for sure.
To get an image out of Google Photos on the web, use the download option in the “three dot” menu:
This will get you the highest quality version available. Do note that it depends on your upload/backup quality settings.
