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Building an artificial sun that looks realistic [video]

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Re: Building an artificial sun that looks realistic [video]

#61

Post by jtanderson »

monktastic1 wrote: post #57
rococode wrote: post #2

In a sci-fi future where people are making long journeys on spaceships I can imagine rooms decked out with these to mimic a natural day/night cycle and outdoor spaces. I remember first seeing lights like these a couple years back before from CoeLux ( https://www.coelux.com ), iirc theirs are very expensive though. Awesome that this guy managed to DIY one!

Riding the coattails of your comment to ask the hive mind: any reason I shouldn't try to build the simpler version from the tutorial using a more powerful (100W) LED from Amazon? https://www.amazon.com/dp/B07T8RDF8F Might not be as awesome as a $60k CoeLux, but for 1000x less cost, maybe it's worth a shot? (Edit: come to think of it, with an 8x10 fresnel lens, it might be way too bright for the size.)

You'd still have to deal with the glare and chromatic aberration from the mirror sheets. Also the area covered would still be confined to the size of one sheet and you'd have to make a "bank" of them to cover any reasonably large area.

Re: Building an artificial sun that looks realistic [video]

#62

Post by db48x »

monktastic1 wrote: post #57
rococode wrote: post #2

In a sci-fi future where people are making long journeys on spaceships I can imagine rooms decked out with these to mimic a natural day/night cycle and outdoor spaces. I remember first seeing lights like these a couple years back before from CoeLux ( https://www.coelux.com ), iirc theirs are very expensive though. Awesome that this guy managed to DIY one!

Riding the coattails of your comment to ask the hive mind: any reason I shouldn't try to build the simpler version from the tutorial using a more powerful (100W) LED from Amazon? https://www.amazon.com/dp/B07T8RDF8F Might not be as awesome as a $60k CoeLux, but for 1000x less cost, maybe it's worth a shot? (Edit: come to think of it, with an 8x10 fresnel lens, it might be way too bright for the size.)

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.

Re: Building an artificial sun that looks realistic [video]

#65

Post by [deleted] »

gruez wrote: post #60
tootie wrote: post #30

Earlier quoted context omitted.

Especially if they emit the UVB light we need for Vit D production

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.

[deleted]

Re: Building an artificial sun that looks realistic [video]

#66

Post by dylan604 »

coryrc wrote: post #53
hendry wrote: post #52

Earlier quoted context omitted.

I'm looking for a warm glow for my dining room. Wdym with "250-400 ways" is that a brand?

autocorrect fail: it's "watts"; 250W & 400W are two common size for metal halide lamps. Unfortunately they are full of mercury and can explode at end of life.

wouldn't that put out a lot of heat? like a lot a lot? that's one of the attractions of LEDs for lighting is they can produce a hell of a lot of light with very little heat coming from the bulb. all of the heat is in the electronics in the back. anything in front of the light will not wilt. of course, i'm thinking in terms of photo/video.

Re: Building an artificial sun that looks realistic [video]

#67

Post by Firerouge »

hinkley wrote: post #64

Why 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.

Re: Building an artificial sun that looks realistic [video]

#68

Post by AceJohnny2 »

csnover wrote: post #22
vimota wrote: post #14

If you're too lazy to build something like this out but like the idea I highly recommend bright LED lighting for the day (explained here: https://www.benkuhn.net/lux/ ). I bought two ~7000 lumens LED corn bulbs and have noticed a huge shift in energy levels from having a brightly-lit room in dark PNW days. I put together a bunch of resources when I was researching buying some here: https://www.notion.so/vimota/LED-Wo…

I did something similar to this but was turned away from using random bulbs off of Amazon since most of them lied about their product performance (advertising peak wattage of all the LEDs and then not driving them at max power), safety certifications (fake UL and ETL markings), and in several cases I could not even find valid business licenses where the companies claimed to be incorporated. I need light for the darkn…

On the higher end, I've been pretty happy with an Eve Light Strip [1]. However that's HomeKit-only. The key option we're looking for is RGBWW (with 2 different "temperature" whites) for a wider range and more natural lighting. We've been considering various more flexible light strip arrangements, but as GP noted, the market is flooded with low-reliability options.

Luckily, we've stumbled upon Sowilo [2], which advertises powerful RGBWW LED strips with appropriate specs (with per-meter max brightness and power consumption listed), provide all the components you need for powering and driving the strips you need, and best of all provide a Hue-integrated controller! (likely from scavenging an actual Hue LED strip controller!). We've ordered a kit last week, and are eagerly anticipating testing out the ~13000lm of purported light.

[1] https://www.evehome.com/en-us/eve-light-strip [2] https://sowilodesign.com/collections/led-strips

Tangentially, we've picked up 4x GE Ultra Bright [3] at Lowes for $10 each to test out the brightness, and those have been great too.

[3] https://www.lowes.com/pd/GE-Ultra-Bright-150-Watt-EQ-A23-Sof...

Re: Building an artificial sun that looks realistic [video]

#69

Post by tootie »

gruez wrote: post #60
tootie wrote: post #30

Earlier quoted context omitted.

Especially if they emit the UVB light we need for Vit D production

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.

There's at least some evidence that LEDs can be more effective than sunlight at synthesizing D. There's a specific wavelength of light that triggers it and I'm not sure if a standard tanning bed emits it.

https://www.nature.com/articles/s41598-017-11362-2

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