4 ms·

That's very weird, does anyone have any insight about this decision on a technical level?

by vmasto 10y ago

shurcooL 10y ago
My guess is that the Night Shift feature depends significantly on the color profile, various options (color temperature, gamma, contrast, sRGB setting, etc.) and calibration of the display. With their own displays, they have full control over that in software, and can produce expected results. It'd be much harder to have predictable results with 3rd party monitors that users configure themselves, so Apple probably opted to outright not support those monitors. It's also a lot easier to test the feature on a limited combination of hardware.
- lloeki 10y ago
  Was about to say basically the same thing, since f.lux works by dynamically altering the colour profile (which results in interesting bugs and glitches here and there). They've been going out of their way to make things work across the board.
  - mikeash 10y ago
    I had to stop using f.lux on my Mac Pro because of this. Every five minutes my screens would blink as it adjusted the color profile. Not quite worth it! If for some reason Night Shift were to cause a similar problem, Apple wouldn't want to put effort into fixing it if it happened with third-party displays. By having an official list, they're free to tell people having problems with other hardware "tough luck, sucks to be you."
copperx 10y ago
I don't think there's one at the moment, but if I were Apple's CEO, I would make all Apple devices have two types of backlights: regular LED backlighting, and LED backlighting with no blue components. A hardware solution would be more costly, but it would be the "Apple" way. Be aware that even if you use Flux or Night Shift your display still emits significant blue light. It could be marketed as a big feature on an Apple keynote, given how much we use devices at night.
- ianai 10y ago
  I think changing to OLED screens is the next logical step toward that? Personally I wish there were display options sans backlight.
  - antfarm 10y ago
    On my white iBook, it was possible to see what's on the screen, even when backlight was turned off, through the translucent apple logo, if the display was lit from the back, by the sun or a lamp. I always wished there was a display that could be lit by an external lightsource, e.g. a library lamp.
- jacobolus 10y ago
  I would love to see a display with, say, 8 primaries instead of 3. With a careful choice of pixel pattern, it should be possible to get much wider color gamut (especially among intense light reds and blue-green colors which are very poorly supported by “RGB” displays), without causing the metamerism problems that very colorful 3-primary displays have. Unfortunately there’s a big chicken–egg problem since images and other content are all created with the expectation of current display technology. They definitely don’t want to completely drop the short-wavelength primary for many purposes, but it would be nice to have a “late night writing mode” where that is possible.
  - illicium 10y ago
    There is no chicken-and-egg problem because the OS already does color management to map your source color space (sRGB, mostly) to your target monitor's color space. If it didn't, you wouldn't be able to view sRGB content correctly on wide-gamut monitors, for example. The real challenge is in developing display backlight and phosphor technology to reproduce colors outside of the standard gamuts.
    - jacobolus 10y ago
      No, there’s a very serious chicken-and-egg problem. The gamut of RGB displays (televisions, projectors, computer and smartphone displays, etc.) has some parts which are very wide and other parts which are very limited. All content produced in the past 20 years expects to be displayed on such displays. If you increase the intensity of the existing “RGB” (orangish-red R, yellowish-green G, purplish-blue B) primaries, you get a display with a substantially similar gamut to existing displays, but with an ability to make certain colors marginally more intense. This is easy for content authors to target using existing workflows, and even potentially possible to adapt existing content for without too much disruption. If you invent a new type of display with a radically different color gamut, and then take existing content and amp up the intensity on hue/value regions with a newly wider gamut, you throw off all of the content creators intentions for color relationships. Total non-starter. What you can do is show old content about the same as it was on past displays, but then there’s not really any advantage to going with the new technology, which is typically going to be more difficult and expensive to produce. A new display needs new content in order to work differently from past displays. (Believe me: I have spent years studying human vision and color reproduction technologies. I’m not just making this up.) If you’re curious about the topic of gamut mapping in general, I recommend this 300-page book, http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470030321.html http://www.wiley.com/WileyCDA/WileyTitle/productCd-047003032... The gamut mapping algorithms used in most common software systems (e.g. Adobe Photoshop) are actually quite poor.
smoser 10y ago
If it works like iOS it changes the tint based on the contents of the screen so it could require some extra processing power to dynamically change the tint level.
kristofferR 10y ago
It's because they have a whitelist of allowed version numbers: https://pikeralpha.wordpress.com/2017/01/30/4398/ https://pikeralpha.wordpress.com/2017/01/30/4398/
apostacy 10y ago
I would strongly suspect that there is absolutely no technical justification for this decision at all. This was a political and marketing decision, to punish customers who use third party devices. This falls neatly into line with Apple's agenda. Apple refused to support TRIM on SSDs, unless you make on small patch to their kext. I would imagine that there is something similar for this feature.

That's very weird, does anyone have any insight about this decision on a technical level?

by vmasto 10y ago

That's very weird, does anyone have any insight about this decision on a technical level?

My guess is that the Night Shift feature depends significantly on the color profile, various options (color temperature, gamma, contrast, sRGB setting, etc.) and calibration of the display. With their own displays, they have full control over that in software, and can produce expected results. It'd be much harder to have predictable results with 3rd party monitors that users configure themselves, so Apple probably opted to outright not support those monitors. It's also a lot easier to test the feature on a limited combination of hardware.

lloeki 10y ago
Was about to say basically the same thing, since f.lux works by dynamically altering the colour profile (which results in interesting bugs and glitches here and there). They've been going out of their way to make things work across the board.
- mikeash 10y ago
  I had to stop using f.lux on my Mac Pro because of this. Every five minutes my screens would blink as it adjusted the color profile. Not quite worth it! If for some reason Night Shift were to cause a similar problem, Apple wouldn't want to put effort into fixing it if it happened with third-party displays. By having an official list, they're free to tell people having problems with other hardware "tough luck, sucks to be you."

copperx 10y ago

I don't think there's one at the moment, but if I were Apple's CEO, I would make all Apple devices have two types of backlights: regular LED backlighting, and LED backlighting with no blue components. A hardware solution would be more costly, but it would be the "Apple" way. Be aware that even if you use Flux or Night Shift your display still emits significant blue light. It could be marketed as a big feature on an Apple keynote, given how much we use devices at night.

ianai 10y ago
I think changing to OLED screens is the next logical step toward that? Personally I wish there were display options sans backlight.
- antfarm 10y ago
  On my white iBook, it was possible to see what's on the screen, even when backlight was turned off, through the translucent apple logo, if the display was lit from the back, by the sun or a lamp. I always wished there was a display that could be lit by an external lightsource, e.g. a library lamp.
jacobolus 10y ago
I would love to see a display with, say, 8 primaries instead of 3. With a careful choice of pixel pattern, it should be possible to get much wider color gamut (especially among intense light reds and blue-green colors which are very poorly supported by “RGB” displays), without causing the metamerism problems that very colorful 3-primary displays have. Unfortunately there’s a big chicken–egg problem since images and other content are all created with the expectation of current display technology. They definitely don’t want to completely drop the short-wavelength primary for many purposes, but it would be nice to have a “late night writing mode” where that is possible.
- illicium 10y ago
  There is no chicken-and-egg problem because the OS already does color management to map your source color space (sRGB, mostly) to your target monitor's color space. If it didn't, you wouldn't be able to view sRGB content correctly on wide-gamut monitors, for example. The real challenge is in developing display backlight and phosphor technology to reproduce colors outside of the standard gamuts.
  - jacobolus 10y ago
    No, there’s a very serious chicken-and-egg problem. The gamut of RGB displays (televisions, projectors, computer and smartphone displays, etc.) has some parts which are very wide and other parts which are very limited. All content produced in the past 20 years expects to be displayed on such displays. If you increase the intensity of the existing “RGB” (orangish-red R, yellowish-green G, purplish-blue B) primaries, you get a display with a substantially similar gamut to existing displays, but with an ability to make certain colors marginally more intense. This is easy for content authors to target using existing workflows, and even potentially possible to adapt existing content for without too much disruption. If you invent a new type of display with a radically different color gamut, and then take existing content and amp up the intensity on hue/value regions with a newly wider gamut, you throw off all of the content creators intentions for color relationships. Total non-starter. What you can do is show old content about the same as it was on past displays, but then there’s not really any advantage to going with the new technology, which is typically going to be more difficult and expensive to produce. A new display needs new content in order to work differently from past displays. (Believe me: I have spent years studying human vision and color reproduction technologies. I’m not just making this up.) If you’re curious about the topic of gamut mapping in general, I recommend this 300-page book, http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470030321.html http://www.wiley.com/WileyCDA/WileyTitle/productCd-047003032... The gamut mapping algorithms used in most common software systems (e.g. Adobe Photoshop) are actually quite poor.

smoser 10y ago

If it works like iOS it changes the tint based on the contents of the screen so it could require some extra processing power to dynamically change the tint level.

kristofferR 10y ago

It's because they have a whitelist of allowed version numbers: https://pikeralpha.wordpress.com/2017/01/30/4398/ https://pikeralpha.wordpress.com/2017/01/30/4398/

apostacy 10y ago

I would strongly suspect that there is absolutely no technical justification for this decision at all. This was a political and marketing decision, to punish customers who use third party devices. This falls neatly into line with Apple's agenda. Apple refused to support TRIM on SSDs, unless you make on small patch to their kext. I would imagine that there is something similar for this feature.