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I'm looking up at my square white ceiling wondering what it would be like if the entire surface was this CoeLux panel. Imagine a vibrant blue sky with a beautiful sun tracking its way across your ceiling all day. I think it could be breathtaking. This is the type of 'simple' invention that you could never really anticipate but changes the future profoundly.
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Do you have a source for that? My understanding is that (a) utilization of dietary vitamin D is significantly lower than naturally produced D (from sun exposure) and (b) vitamin D is one of several micronutrients produced from sun exposure.
> My understanding is that (a) utilization of dietary vitamin D is significantly lower than naturally produced D (from sun exposure)... The end product of UVB irradiated skin (i.e., sunlight) is vitamin D3. (D3 is "activated" locally in tissues utilizing it.) Ingested D3 supplements effectively add to the body's supply, though the optimum intake is controversial and varies among individuals. One difference between su…
So the advise is to take D supplements only if recommended by a doctor.
I'm looking up at my square white ceiling wondering what it would be like if the entire surface was this CoeLux panel. Imagine a vibrant blue sky with a beautiful sun tracking its way across your ceiling all day. I think it could be breathtaking. This is the type of 'simple' invention that you could never really anticipate but changes the future profoundly.
Well, maybe in one more generation once the resolution becomes higher.. and adding hand tracking.. and a UV lamp on a servo..
...and obligatory musical reference: https://www.youtube.com/watch?v=txPqV0lZaSE
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> My understanding is that (a) utilization of dietary vitamin D is significantly lower than naturally produced D (from sun exposure)... The end product of UVB irradiated skin (i.e., sunlight) is vitamin D3. (D3 is "activated" locally in tissues utilizing it.) Ingested D3 supplements effectively add to the body's supply, though the optimum intake is controversial and varies among individuals. One difference between su…
It is unfortunate that "vitamin D" is called "vitamin" since it is in fact a hormone. As with most hormones, their effect depends on many factors including the number of receptors on target cells that can change significantly increasing or decreasing sensitivity to D. That itself is poorly understood and it is unknown how long-term consumption of D supplements in what ever form with little exposure to real Sun affect…
Presumed deficiency of D (per lab studies) is quite common here and supplementation is usually recommended for optimum health. Besides location, lifestyle factors often reduce sun exposure increasing chances of low D level.
There are tradeoffs involved with most recommendations. The common advice to avoid UV exposure re: melanoma risk has propelled manufacture of sunscreens into a big industry. Sunscreens filter out nearly all UVB, and interfere with forming D. Ironically, low body stores of D may increase cancer risk according to some studies. BTW my dermatologist knows about that, nonetheless advocates minimizing cancer risk, worrying less about vitamin D deficiency or risks of supplementation.
Indigenous Alaskan populations were always vulnerable to D deficiency yet it was uncommon, probably associated with their diet, rich in the oils of sea-going animals, known sources of D. Out of curiosity, a while back based on published info I calculated their intake of vitamin D was roughly 1500-2000IU/day. This seems consistent with opinions of some researchers re: appropriate intake level (don't have the references at hand--I can locate them if there's interest).
The jury's still out on vitamin D in terms of its functions and dietary requirement. It is a fascinating story that with any luck will be at least better resolved in my lifetime.
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While this is is nice, the main breakthrough of CoeLux is the simulation of Rayleigh scattering, not just a bright diffused light.
And while fun to read, the cheap trick above doesn't have the right lightwaves to make you feel the same.
In computer graphics, if you want to get "daylight" illumination for cheap, you simply use two lights - one white-to-yellowish directional and one bluish hemispherical:
http://threejs.org/examples/webgl_lights_hemisphere.html
You only compute expensive scattering if you need volumetric effects (e.g. god rays or atmospheric fog blueing things far away, on the order of at least hundreds of meters).
But here for simple indoor lighting, you don't really need volumetric effects. You just need proper light color coming from roughly appropriate directions - one strong white-to-yellowish light (coming from uniform direction) that will cast hard shadows and one weaker bluish diffuse light (coming from many directions) that will cast soft shadows.
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And while fun to read, the cheap trick above doesn't have the right lightwaves to make you feel the same.
I have a suspicion you may not even need scattering to achieve similar psychological effects. In computer graphics, if you want to get "daylight" illumination for cheap, you simply use two lights - one white-to-yellowish directional and one bluish hemispherical: http://threejs.org/examples/webgl_lights_hemisphere.html You only compute expensive scattering if you need volumetric effects (e.g. god rays or atmospheric f…