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Re: Next step for DAP Ambient Light Events

From: Tab Atkins Jr. <jackalmage@gmail.com>
Date: Thu, 13 Sep 2012 12:38:33 -0700
Message-ID: <CAAWBYDAgtQc2vgvtCfWxTYjzdFiRMsj3CSKPiFW0bRY4zOrVsw@mail.gmail.com>
To: Chris Lilley <chris@w3.org>
Cc: Doug Turner <doug.turner@gmail.com>, "SULLIVAN, BRYAN L" <bs3131@att.com>, "Tran, Dzung D" <dzung.d.tran@intel.com>, Fran├žois REMY <fremycompany_pub@yahoo.fr>, Marcos Caceres <w3c@marcosc.com>, Doug Turner <dougt@mozilla.com>, CSS WG <www-style@w3.org>, "public-device-apis@w3.org" <public-device-apis@w3.org>
On Thu, Sep 13, 2012 at 12:33 PM, Chris Lilley <chris@w3.org> wrote:
> On Thursday, September 13, 2012, 9:18:15 PM, Tab wrote:
>>> Obviously these levels depend on the adaptation state of the user, which is unknown.
>>>
>>> As an example, at typical ambient levels, a monitor at 120-150 lux would be seen as normally illuminated, and 300 as very bright.
>>
>> I believe you're talking about the lux *produced* by the screen.  I
>> agree, a screen pumping out 300lux would be very bright.
>>
>> This topic, though, is about the ambient light level.
>
> Yes. You may have missed the 'adaptation state' part of the introductory sentence.
>
> If the lights are mostly low or off, the room is illuminated by LEDs on equipment and such; the major adaptive stimulus is the screen.
>
> Now open the curtains, and suddenly the major adaptive stimulus is the window plus the light bouncing round the room. Which is the situation mostly described in textbooks (the object being viewed is not the major adaptive stimulus).
>
> Nowadays though the former situation is increasingly likely (and ambient sensors are often angled to avoid light from the screen).

No, I got that, I just don't understand how it's relevant.  If you
assume that the user is adapted to the current light level, then the
ambient light level is what you want to know in this API, so you can
adjust your own colors and light production in your page.

~TJ
Received on Thursday, 13 September 2012 19:39:21 GMT

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