4
\$\begingroup\$

If a laptop used for photography editing needs color accuracy, but only scores a color gamut of 90% sRGB and 65% Adobe RGB, can it still emit 100% sRGB and 100% Adobe RGB on a stand-alone monitor that is rated 100% sRGB and 100% Adobe RGB?

In other words, must the source device (the laptop) be rated 100% RGB in order to output 100% RGB on attached devices (the external monitor, not to be confused with the laptop's own screen)?

\$\endgroup\$
4
  • 1
    \$\begingroup\$ The rating for the laptop is for its output to built-in display. The GPU itself can quite likely do better than this on a fully-calibrated external. \$\endgroup\$
    – Tetsujin
    Mar 13, 2023 at 8:45
  • 1
    \$\begingroup\$ I’m voting to close this question because it has nothing to do with photography. \$\endgroup\$
    – Tetsujin
    Mar 13, 2023 at 8:45
  • 1
    \$\begingroup\$ @Tetsujin That's the whole point of the question. Hope you could provide a formal answer. \$\endgroup\$
    – user610620
    Mar 13, 2023 at 23:06
  • \$\begingroup\$ Then make an answer \$\endgroup\$
    – user610620
    Mar 17, 2023 at 22:20

2 Answers 2

6
\$\begingroup\$

If you ask this because you want to do photo retouching work on the gaming laptop, the answer is yes. The color space of sRGB or Adobe RGB is coded into the file. The rendering device (display, printer, projector) which displays the colors then tries its best to reproduce the colors in the specified color space.

So if your internal display does not cover enough of your target color space, you can always attach a display that does - as long as your graphics card is able to cope with the rest of the display's specifications (refresh rate, resolution).

Back in VGA days with analogue signals, a really bad graphics card could ruin your color rendition. Nowadays, with digital signals (hdmi, display port, etc) this would only be a theoretical issue if the signal processing is really broken. I experienced things like flickering if graphics card and display had some real issue with each other, but never really skewed colors. And even that is fairly rare. In the last 5 years in IT, I had one display that would not work with a certain Apple laptop no matter what we tried, so I would rate that rather as anecdotal.

Note: You still will have to calibrate the combination of GPU and display to have your colors as precise as possible and maybe to disable any tools within the GPU's driver that might do automatic brightness control or "night shift" color shifting, but that was not really part of the question.

So, to sum it up:

  • Only the output device is the real limit of the color space coverage
  • The graphics card is not a limiting factor in this instance
  • Software can ruin your color space coverage (Night Shift, Fancy GPU Driver Tools that influence color rendition)
  • You still might need to calibrate your display to fully utilize it's color space coverage.
\$\endgroup\$
9
  • 1
    \$\begingroup\$ @Rafael Good point. Rephrased it a bit. \$\endgroup\$ Mar 14, 2023 at 7:14
  • 1
    \$\begingroup\$ @user610620 Yes, but we try to answer the questions not only for you, but also for anyone else reading here. So we usually try to include as much context as possible for the answer to be useful in a wider scope. ;) \$\endgroup\$ Mar 14, 2023 at 7:25
  • 1
    \$\begingroup\$ @user610620 If your computer's documentation doesn't include that information, then see if you can find what GPU the computer has inside it and check the documentation from the GPU's manufacturer. There should be a spec that lists what resolutions and refresh rates the video port (HDMI, DP, etc.) supports. \$\endgroup\$
    – Michael C
    Mar 17, 2023 at 12:13
  • 1
    \$\begingroup\$ @user610620 Since you have not specified the laptop in question, nor the external display you are considering, nor the type of connection (HDMI, DP, TB, etc.) you plan to use to connect an external monitor we can't look that up for you. \$\endgroup\$
    – Michael C
    Mar 17, 2023 at 12:19
  • 1
    \$\begingroup\$ It's always about specifics when talking about whether a specific GPU can output at a specific resolution and frame rate. \$\endgroup\$
    – Michael C
    Mar 18, 2023 at 17:05
2
\$\begingroup\$

A computer's graphics processor simply processes/regurgitates color information to the maximum accuracy it is capable of (e.g. 8bit, 10bit)... i.e. it can fully replicate any color space (overall size/area) with differing levels of accuracy for the colors w/in that space.

If you want/need the capability of a larger color space, then you need a monitor capable of displaying those colors.


EDIT: Color gamut is a characteristic of a display; it is an output limitation, not an input limitation.

E.g. a GPU is an input (to the monitor), it is not generating colors perse , it is simply sending color numbers to the display (what a GPU actually/primarily does is calculate 3D graphics using linear algebra). The monitor is the output, and in the end it's color accuracy is primarily limited by the quality of the pixels it was made with.

Similarly a printer is gamut limited by the quality/number of inks it has, and it's ability to accurately mix them; not by the color numbers sent to it. But a printer is also an input to the print/paper; and the ultimate print output gamut is limited by the combination of the paper and the printer together.

All output devices have their own gamut; the limit of colors they can reproduce regardless of the numbers they are given. And a gamut (E.g. sRGB) is just a way to describe a region of the visible RGB spectrum. A display could be capable of reproducing all of the sRGB gamut, plus most of adobeRGB, plus some of ProPhoto RGB... calling it an 85% adobe RGB display is an oversimplification.

enter image description here

\$\endgroup\$
8
  • \$\begingroup\$ When you say "computer's graphics processor regurgitates color information to its max capability", please re-phrase in Adobe RGB and sRGB terms, not 8bit or 10 bit since those weren't the question. Will a 100% RGB monitor be constrained to the GPU's own 65% RGB color gamut, for example? \$\endgroup\$
    – user610620
    Mar 13, 2023 at 22:05
  • 1
    \$\begingroup\$ A GPU has very little to do with color or color accuracy. It does not translate/convert/or calculate colors. At most it will shift colors based upon a color look up table (LUT). \$\endgroup\$ Mar 14, 2023 at 13:36
  • \$\begingroup\$ @user610620, that's the core of your confusion: GPU doesn't "know" colors, color spaces is not its domain. GPU can only command to the display things like "give me full red!". A better display will show "redder" red on this same output than your laptop. This is why you can attach a better display and get better results. But: your software/OS (which is the only thing that knows which colors should be shown) needs to know the actual capabilities of the display (how red is max red) in order to show colors accurately. Hence profiling/calibration, which is another topic (well covered here). \$\endgroup\$
    – Zeus
    Mar 14, 2023 at 23:37
  • \$\begingroup\$ ...at the same time, GPU bits are somewhat important: they determine how many colors GPU can produce (e.g. 8 bit means 2^(3*8)=16M colors), but which physical color each of them will be depends on the display. \$\endgroup\$
    – Zeus
    Mar 14, 2023 at 23:45
  • 1
    \$\begingroup\$ @user610620, there is no GPU gamut. At a given time (e.g. when showing a photo), two gamuts (or else color profiles) exist: the source one, embedded or assumed in the photo, which tells what colors are desired, and the output one, that of your physical display. If you need to know more, you can search this site about "color profiling", or ask a new question. This question specifically asks about the output profiles, and the answer is yes, they can and will be different for each attached display, and the software should better know about it in order to display colors correctly. \$\endgroup\$
    – Zeus
    Mar 17, 2023 at 7:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.