Messages in this thread | | | Date | Fri, 31 Mar 2023 10:59:51 +0200 | Subject | Re: [PATCH 3/3] arm64: dts: qcom: sm7225-fairphone-fp4: configure flash LED | From | "Luca Weiss" <> |
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Hi Pavel,
On Thu Mar 23, 2023 at 8:54 PM CET, Pavel Machek wrote: > Hi! > > > > > > I'm pretty sure the flash is not yellow. > > > > > > The marketing term is Dual LED flash or Dual-tone flash, one LED is a > > > blue-ish white and one is a yellow-ish white, but from what I can tell, > > > in the original code it's always referred to as white and yellow so I > > > also followed that here. > > > > > > Also the LEDs are right next to each other so in practise for torch just > > > both go on, and for camera flash I cannot really tell you but I guess > > > it's doing something there with the camera tuning. > > > > > > See also this picture: > > > https://shop.fairphone.com/media/catalog/product/cache/b752d78484639b19641a8560800d919d/p/_/p_5b_main_camera_back.jpg > > > > > Hi Pavel, > > > > Luca is right. It is normally called dual CCT (Correlated Color Temperature) > > flash LED. It has 2 LEDs, one is with higher CCT (~6000K) so it looks like a > > white LED, another is with lower CCT (~2000K) and it looks like a yellow > > LED. I am not an expert of this but my understanding is the camera tuning > > process normally adjusts the brightness of the two LEDs and enables them to > > get different CCT for different snapshots. > > I believe this is normally called "warm white" and "cool white", no? > Yellow would be monochromatic light at cca 575nm, see > https://en.wikipedia.org/wiki/Shades_of_yellow .
I don't really have any more information I can provide right now. If you feel it should be called warm white and cool white, feel free to send a patch changing it.
I'm personally okay with it being called white & yellow since that seems to be the term used in (downstream) software for these kinds of leds.
Regards Luca
> > If we need to add some defines for that, lets do that. > > BR, > Pavel > -- > People of Russia, stop Putin before his war on Ukraine escalates.
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