6

Currently screen shots are coerced into standard color ranges, meaning you cannot take an accurate screen shot of the screen when ultra bright HDR content (or possibly ultra black HDR content) is shown.

Is there any solution for this, at present?

4
  • 2
    Which Mac do you have? Newer ones are capable of P3 by default, which is an 'HDR' - 'HDR' isn't a standard, it's marketing-speak covering many similar [but different] standards. If you take a screenshot & the colours change, you have a profile mismatch; Chrome & Firefox are poor at this, Safari is better, but such as YouTube content is often delivered with the 'wrong' profile.
    – Tetsujin
    Commented Sep 17, 2022 at 6:16
  • I have an Apple Silicon MBP. I don’t think there is a profile mismatch; i just think that standard screenshot tools do not capture ranges outside of sRGB
    – Alan H.
    Commented Oct 6, 2022 at 17:33
  • The built-in screenshot captures with your display's currently-assigned profile -i.sstatic.net/P3kF5.jpg
    – Tetsujin
    Commented Oct 6, 2022 at 17:49
  • OK but using the built-in screenshot tool, using my built-in laptop monitor, on HDR content produces non-HDR content with 'Laptop LCD' profile
    – Alan H.
    Commented Oct 6, 2022 at 20:06

2 Answers 2

4
+100

Ah, I can repro this, and have a workaround. Strangely, it seems like if you take an "entire screen" screenshot, e.g. with 3, it compresses the colour gamut down to sRGB:

screenshot of wide-gamut.com not indicating a wide colour gamut

But if you take a screenshot of part of the screen or a specific window, e.g. with 4, it leaves it in your display's colour profile:

screenshot of wide-gamut.com indicating a wide colour gamut

So you can simply use 4 and drag the crosshairs to cover your entire display. Strange difference, but there you have it. I can verify the different profiles using Get Info in Finder:

two Get Info windows from Finder, displaying details about the images, one in sRGB colour profile, and the other in "Color LCD"

I'm also using a MacBook Pro with M1, and these screenshots are of wide-gamut.com/test

3
  • Wow! Holy sh.. batman. It does. I can repro that here by simply screen-shotting your post with c/s/3 & comparing to c/s/4. c/s/3 loses the W. My only 'excuse' for not knowing that is I almost never use the c/s/3 screenshot, so I've simply never had occasion to compare. Nice bit of discovery there! :)
    – Tetsujin
    Commented Nov 16, 2022 at 18:53
  • 1
    This answer is wrong, at least on MacOS 13.1. Regardless of <kbd>⌘</kbd><kbd>⇧</kbd><kbd>4</kbd> or <kbd>⌘</kbd><kbd>⇧</kbd><kbd>3</kbd> the resulting PNG file is 8 bits per channel. Apple's own site claims the display supports 1 billion colors. It requires more then 8bits per channel to support more than 16 million colors. The screenshots are being compressed to 8 bits but then have their color space set. But that's a lossy screenshot.
    – gman
    Commented Jan 14, 2023 at 20:03
  • 1
    Note: Finder will not tell you the bit depth but Preview will. Open the file, press Cmd-I for info. Click the 2nd icon. You'll see the files are 8bit depth. For a PNG they'd need to be 16bit to not be lossy.
    – gman
    Commented Jan 17, 2023 at 18:23
1

Using answer space for image inlining…

I cannot repro your issue.

The following tests were all done on a non-colour-managed M1 iMac [with a Display P3 screen], using the Apple-supplied default display profile & Safari [built primarily on WebKit].
My main work Mac is fully colour-managed so I have checked my results on there - but it is qualified only up to Adobe RGB 98, a smaller gamut but still a lot larger than sRGB & one which is widely used for professional photographic work. I can still see that the images are 'in the ballpark'

Using example images from WebKit org & screenshotting each, rather than importing the original files. This gives them all the same colour profile, that of the Mac's display. [I've then had to drop them to smaller jpg to be able to upload here, but that hasn't affected the profile or colour repro.]

sRGB for comparison of non-HDR image
enter image description here

Display P3 - Apple's native HDR display format
enter image description here

Screenshot of screenshot overlaid on original Display P3
enter image description here

If especially the yellows & oranges in these images look the same between the sRGB & P3 variants, then there is a profiling issue in your browser. Try Safari, which has good, usable defaults.

To investigate further we need to know your workflow - what the input profiles are, what file types, what app is being used to view & what colour settings it's using.
Browsers such as Chrome & Firefox have some odd defaults which may need changing. Photoshop is frequently set up wrongly for colour workflow by unsuspecting users.

4
  • 1
    Is all this about colour profiles relevant? Is it not just an 8-bit vs 10-bit issue? To my mind, a screenshot should have each colour component with the same values as sent to the screen. Whilst screens (and drivers and apps) may support 10-bit colour, screenshots are always produced as 8-bit png - so having a smaller dynamic range than what was sent to the screen. Or am I way off track?
    – Gilby
    Commented Oct 11, 2022 at 9:51
  • @Gilby - The difference between 8 & 10 [or more] bit is granularity, not overall gamut. My camera uses 12-bit images. My display only has 8-bit resolution. I can still see all the gamut, I just don't have the smoothest experience when shading very gently on a smooth vignette. This causes banding - en.wikipedia.org/wiki/Colour_banding The banding in the sky photo is kind of artificially over-cooked. If you take that & switch it to 16 bit, blur it then switch it back to 8, the banding is nowhere near as severe as the example.
    – Tetsujin
    Commented Oct 11, 2022 at 9:59
  • 8-bit, switched to 16, not very carefully blurred, then switched back to 8-bit. i.sstatic.net/BmvfD.jpg You can't do the job nearly so well if you keep it at 8 bit right through, but the single conversion back to 8 at the end is nowhere near as damaging as the original implies. This, in effect, is what a screenshot does - bit-reduces right at the very end, so the colours should be fine, just any vignette will band a bit.
    – Tetsujin
    Commented Oct 11, 2022 at 10:19
  • I will think about that. Your 8>16>blur>8 image is interesting. Nearly all artefacts gone (I see a slight purple banding).
    – Gilby
    Commented Oct 11, 2022 at 21:20

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .