Facebook, Firefox browser, and wide gamut monitor users

[pschlute]

Can someone do a favour for me. I recently posted a picture to my facebook page, and noticed that the image was very over-saturated. I use a wide gamut monitor, and Firefox browser, correctly set up for colour management.

Now I know that FB strips out a lot of the metadata from an image, but until now had never noticed a colour shift.

Perhaps someone can do a test picture themselves and tell me if they notice similar issues.

Many thanks.

[Manfred M]

I just posted two images to Facebook. One used the sRGB colour space and the other was Adobe RGB. I do all my work on a Wide Gamut screen (Adobe RGB compliant).

Under normal circumstances, an Adobe RGB image would tend to look "muddier" than an sRGB one, if no colour management is applied by either the host (Facebook) or the browser (Firefox, in my case).

I have seen problems when I accidentally use the the "Assign Profile" rather than the "Convert to Profile" command in Photoshop.

Side-by-side, both images looked identical, so at least in this case, I saw no colour issues.

[pschlute]

The plot thickens. It must be down to my Firefox settings.

The same image shows correctly in Flickr , but not in Facebook. I am assuming that is because FB strips out the colour profile tag.

But I never had a problem before. time to check my Firefox settings

[pschlute]

Update..... the latest Firefox version 77 has a bug.

When viewing untagged jpeg or png images the setting "gfx.color_management.mode" = 1 no longer displays those images correctly.

See here...... https://cameratico.com/color-management/firefox/

As long as you are viewing images which are tagged you wont see any difference. But as Facebook strips the tag out of an image, all your friends will have very red faces when viewed on a wide gamut monitor.

[xpatUSA]

Update..... the latest Firefox version 77 has a bug.

When viewing untagged jpeg or png images the setting "gfx.color_management.mode" = 1 no longer displays those images correctly.

See here...... https://cameratico.com/color-management/firefox/

As long as you are viewing images which are tagged you wont see any difference. But as Facebook strips the tag out of an image, all your friends will have very red faces when viewed on a wide gamut monitor.

Thanks for heads-up, Peter.

I'm on V.76, so I'll leave it there and I quit Facebook long ago ...

[DanK]

Thanks for pointing this out. I ran the test he linked, and sure enough: the untagged sRGB image looks like proPhoto on my wide gamut monitor.

But here's the puzzle: I then slid the browser window over to my cheap sRGB second monitor, and the same thing shows up. The colors look different from one monitor to the other, of course. But on both monitors, the first and second sets of bars look the same, that is, the second set is not one seamless color on the sRGB monitor either.

[pschlute]

Even more confusing..... I can see that my last photo uploaded to FB has had the profile stripped, but that some previous ones have not ? If I download the photos from FB and check for a tagged profile the most recent one has no profile, but the previous two are showing as "sRGB IEC61966-2-1 black scaled". No idea what that "black scaled" part of the profile designation is ? It is something that FB have changed to the profile designation.

[pschlute]

the second set is not one seamless color on the sRGB monitor either.

Try the test in another browser. If I look at the test page in Microsoft Edge, the second set of bars are seamless on my monitor in both AdobeRGB and sRGB gamut settings. On Firefox they are not, confirming that the "bug" is present.

[DanK]

Try the test in another browser. If I look at the test page in Microsoft Edge, the second set of bars are seamless on my monitor in both AdobeRGB and sRGB gamut settings. On Firefox they are not, confirming that the "bug" is present.

both of my monitors are fine using Edge.

[xpatUSA]

... If I download the photos from FB and check for a tagged profile the most recent one has no profile, but the previous two are showing as "sRGB IEC61966-2-1 black scaled". No idea what that "black scaled" part of the profile designation is ? It is something that FB have changed to the profile designation.

Also known as Black Point Compensation (BPC).

It means that FB took your source image and noted that the darkest darks are, say, 0.1 relative to a brightest bright of 1.0. Then FB assumed or measured the destination image shown on the average Joe's monitor and determined that the blackest black it can manage is, say, 0.3. So the matrix in that ICC profile squeezes up all the tones from your source image before showing it on your monitor. See fig.4 page 5:

http://www.color.org/WP40-Black_Poin...2010-07-27.pdf

HTH

[pschlute]

Thank you Ted. So I am right in the assumption that FB changes my tagged profile to suit what it expects the majority of its viewers will see.

Still dont understand why the latest image I posted has its profile tag completely stripped altogether.

I know FB is not a "photography" website, but there are a few groups I am part of on there that are photography related.

[Manfred M]

I know FB is not a "photography" website, but there are a few groups I am part of on there that are photography related.

I believe the advice of posting all images in the internet as sRGB is the best advice one can give. That reduces any issues with the host site stripping out the metadata and applying an incorrect profile.

[pschlute]

I believe the advice of posting all images in the internet as sRGB is the best advice one can give. That reduces any issues with the host site stripping out the metadata and applying an incorrect profile.

But that is the odd thing Manfred. I only use sRGB when posting to the web, but FB seems to either strip it or substitutes a version of sRGB of its own.

[pschlute]

Update...... Firefox released a new version 78.0.1 (64 bit)

This seems to have fixed the problem with untagged images showing oversaturated on a wide gamut screen.

[DanK]

Update...... Firefox released a new version 78.0.1 (64 bit)

This seems to have fixed the problem with untagged images showing oversaturated on a wide gamut screen.

I just checked it with this test, https://cameratico.com/tools/web-bro...nagement-test/, and it does seem to be fine now. Thanks for posting.

[xpatUSA]

I just checked it with this test, https://cameratico.com/tools/web-bro...nagement-test/, and it does seem to be fine now. Thanks for posting.

Excellent! Now I can click yes when the update dialog appears, thanks to Peter.