Different colours JPG and TIFF

Software darktable
1

Hi,
I have the final image edited in Darktable 4.6.1.
I export it in JPG, sRGB for the internet and TIFF, Adobe RGb for printing.
The colours are different.
When I open them with Photoshop:
In JPG, the colours are the same than the edited ones.
In TIFF, Adobe RGB they come out totally different, contrasts are lost, etc.
Thank you.

2

It could be that the app you use to view the images not being colour managed; or there is some other colour management issue on your system.

You could import both exported files back into darktable. Provided that the profile was embedded into the exported files, if they look correct, it’s probably a colour management issue (outside of darktable).

The latest version is 4.8.1, not 4.6.1.

1 Like
3

I open them with Photoshop.

4

Do they have an embedded profile? Darktable should add one.
Can you post a problematic image + sidecar + your export settings? Do you export at full size, or at different resolutions (pixel dimensions)? Is high-quality resampling enabled in the export module?

5

_MG_0221
_MG_02212952Ă—1969 3.36 MB

Jpg 8bits
100ppp
sRGB internet

TIFF
300ppp
Adobe RGB

6

Tiff is not possible to send it

7

Perhaps, in order to have fewer variables/unknowns, you could export them both as JPG, one with sRGB, another with AdobeRGB profile.

2 Likes
8

It might be that its an issue with what you are doing on import or at least what is happening based on these sorts of setting that are found in PS…

I don’t have PS but this screen shot from a post shows some of the PS color management configuration/settings that you will need to configure and respond accordingly if prompted to get the result you want… the text are not my comments just embedded in as part of the screen shot from a post where a similar problem was being discussed

image

1 Like
9

Good advise…
I made several combinations.
The only one that is exactly Draktable edition is JPG sRGB 100.
Then, almost TIFF Adobe RGB 100 and TIFF sRGB100
The other combinations JPG ADOBE RGB 300, JPG sRGB 300, TIFF RGB 300 or 100, etc. are totally different, no contrasts.

10

What kind is your monitor? Can he represent Adobe RGB or is he only suitable for the smaller color space sRGB?

1 Like
11

The answer is in your original post. If you view both the JPEG and the TIFF in an image viewer without color management, the images will be displayed in their respective colorspaces, which are different. I’d guess your monitor gamut is closer to sRGB, hence the particular difference you report.

If the respective profiles are embedded, try displaying them in one of the modern web browsers, either Firefox or Chrome. Chrome color-manages to sRGB by default, and I think Firefox does same, so they should look identical there.

However, what you really need is a calibrated display profile, and that profile loaded into all the software you use for viewing. And, if a particular software doesn’t recognize display profiles, discard it. I’m just kidding, kinda… :crazy_face:

4 Likes
12

Additionally, exporting in Adobe RGB for printing makes only sense, when your editing display supports Adobe RGB and the printer has a color space including colors outside sRGB (and inside Adobe RGB). But even then, there are no (few) printers that can print the whole Adobe RGB color space. Therefore, some gamut corrections have to be made during printing. In this case it might be better to do this in the smaller sRGB color space before export and print accordingly.
Some explanations can also be found here.

2 Likes
13

As @ggbutcher already suggested you should check whether you have 1) calibrated and profiled display; 2) your authoring and viewing software is using that profile.

Here is my favorite test for web browser colormanagement:

The same images of course can be downloaded and used to check any image viewer.

1 Like
14

What do you mean by those combinations of file format + colour space name + number, like JPG sRGB 100 and TIFF RGB 300?

15

From my dabbling a very long time ago, these may be possible explanations (besides the ones already suggested):

  1. Working spaces are different from display spaces. I do not think Photoshop allows one to choose the display space. There may be another configuration you have to set, other than color settings and dealing with the embedded profile mismatch.
  2. Photoshop may rely on the Windows OS to do the colour management for the desktop environment and the monitor, respectively.
  3. The monitor itself may require specific drivers and its own LUT. Same with the video card if you have one.

I will leave the details to our resident experts… :stuck_out_tongue:

1 Like
16

Here’s a more comprehensive test:
https://displaycal.net/icc-color-management-test/

2 Likes
17

Thank you !

18

Thank you!

19

Thank you all.

I carefully read all the posts.

  • My Canon camera is set to Adobe RGB.

  • Photoshop is set to Colour RGB mode.

  • Screen:

  • Colour format: RGB
  • Colour space: SDR.
  • Bit depth: 8bits

Using the same screen, the image quality varies depending on the format and space that is exported from Darktable. JPG is perfect and TIFF does not.

Thank you.

20

With current master I have exported:

  • JPG sRGB
  • JPG Adobe RGB
  • TIFF sRGB
  • TIFF Adobe RGB

I have opened the 4 images on the same screen with:

  • Loupe (default image viewer GNOME 47) - no difference
  • GIMP - no difference
  • Rawtherapee - no difference

And when I say no difference, I really mean it, viewing each to top of the other it is just impossible to see a difference as if the images where all the same.

So nothing looks broken on my side.