Earlier quoted context omitted.
FWIW there's not evidence vitamin D supplements have any health impact (asides from crickets).
Aside from _in_ crickets experimentally, or aside from crickets as in you hear nothing?
rickets, not crickets
Building an artificial sun that looks realistic [video]
111–120 of 129 posts
Re: Building an artificial sun that looks realistic [video]
#112Earlier quoted context omitted.
I thought the official advice was to get supplemental vitamin d through oral supplements, rather than through artificial UV lamps? https://www.nhs.uk/live-well/healthy-body/how-to-get-vitamin... >Using sunbeds isn't a recommended way of making vitamin D.
FWIW there's not evidence vitamin D supplements have any health impact (asides from crickets).
I think you need to add "among people with sufficient levels of vitamin D" to that statement.
It follows almost from definition that if you are deficient in something, supplementing that something is beneficial. There might be some exceptions, but then we've really just got deficient defined poorly or no effective method of supplementation.
Re: Building an artificial sun that looks realistic [video]
#113Anyone familair with this: https://www.tate.org.uk/whats-on/tate-modern/exhibition/unil... I saw it at the Tate Gallery. It was one of the most impressive art installations I have ever witnessed.
Ah, I have fond memories of that, a favourite for me too. I wish it was a permanent exhibit. His exhibition there last year was just great too with lots of light used in different ways.
Re: Building an artificial sun that looks realistic [video]
#114Anyone familair with this: https://www.tate.org.uk/whats-on/tate-modern/exhibition/unil... I saw it at the Tate Gallery. It was one of the most impressive art installations I have ever witnessed.
Also I think those are sodium lights. More or less a single wavelength, hence the monochrome (yellow and black) look. Just about as far opposite to daylight as you can get!
It was a semicircle against a mirrored ceiling which is a neat trick to double the effect. People naturally lay on the floor like being on a beach and saw themselves reflected back way overhead.
Re: Building an artificial sun that looks realistic [video]
#115Couldn't this potentially dangerously amplify ambient RF if you follow the author's advice of re-using an antenna dish & covering it with a non-conductive reflective vinyl coating?
The 3M ‘chrome’ vinyl wrap is conductive.
Re: Building an artificial sun that looks realistic [video]
#116Part of me is like, no way I want that, it isn't natural. And the other part is like, yes way I want that, what I do with indoor lighting isn't natural anyways!
Re: Building an artificial sun that looks realistic [video]
#117Earlier quoted context omitted.
lenses cause chromatic abberations though, the red/yellow halo around the beam you see in his cheaper version at the end.
I have a chromatic film on my actual windows because I like the effect so there's technically a market for it , especially if it makes it cheaper and smaller
I am really curious about this -- do you have it just for the effect? What does it look like?
Re: Building an artificial sun that looks realistic [video]
#118Earlier quoted context omitted.
Don't forget that the volume of the device has a cost too. The video shows the construction of a really really nice, but takes up the whole hallway outside that room. Most of the time you'd probably prefer to use your hallway for walking in. On the other hand, maybe your house has an attic above one of your rooms that; there will be a lot less opportunity cost to using up that volume.
Use Fresnel lenses with a shorter focal length and reduce the depth. It would be useful to start with a standard home-type window from, say, Home Depot, and build a unit about 120mm deep using multiple shorter focal length Fresnel lenses.[1] Then, in a basement or windowless room, mount some of these into a wall. Add curtains. Nice if your home office or workshop is in a basement. This has commercial applications. Ho…
Keep watching the video - he builds Fresnel lens versions at the end of the video.
The satellite dish is more dramatic so I don't blame him for leading with it :)
Re: Building an artificial sun that looks realistic [video]
#119Anyone familair with this: https://www.tate.org.uk/whats-on/tate-modern/exhibition/unil... I saw it at the Tate Gallery. It was one of the most impressive art installations I have ever witnessed.
Yes that's exactly what I thought of seeing this! It was so miserably cold and sleeting the day I went and inside it felt like an oasis. Everyone lying on the floor basking in front of that giant sun.
Re: Building an artificial sun that looks realistic [video]
#120Why do fresnel reflectors seem to be so hard to find? Seems like they’d be a good option here.
I wonder this as well, perhaps it's a problem related to manufacturing shrinking sized concentric steps? If my understanding is correct, fresnel lenses effectively operate as a larger lense surface by concentrating light with flat or curved steps getting smaller in size packed towards the core.
Unless I’m mistaken, you should be able to invert a fresnel lens stamp, make the same plastic lens and then silver it, so now it’s a concave mirror instead of a convex lens.