Have SAD? Want some Sun? Just DIY one.

September 8, 2022 6:19 AM

Building an artificial sun that looks unbelievably realistic... - YouTube Brought to you by Over Engineering.
posted by zengargoyle (23 comments total)

Wow! This is great. But by "artificial sun" they really mean "artificial sunlight from a cleverly-designed bright light that looks like a window." I was expecting some kind of glowing orb and not a fake window, but still.
posted by emelenjr at 6:45 AM on September 8, 2022 [1 favorite]

This is amazing and kinda depressing?

I suppose this will help when the remaining human survivors move underground to avoid the rising sea levels and rising temperatures on the surface of Earth. Elderly folks will be able to tell young children of a time when there actually was a sun that was warm and welcoming... and didn't require 70000 sunblock.
posted by greenhornet at 6:50 AM on September 8, 2022 [2 favorites]

greenhornet, there are lots of beautiful places on the earth today where the sun is only out for a handful of hours each day during the depths of winter, so I think there's plenty of reason to want something like this even before we all move into underground bunkers :)
posted by wesleyac at 7:26 AM on September 8, 2022 [9 favorites]

Wow! I am very excited about this. I'm an escape room designer, and my mind is just filling up with ways to use something like this. I guess I'd be a little concerned about the long-term maintenance of the water-bearing parts, but dang this would be a cool effect if used properly.
posted by aubilenon at 7:39 AM on September 8, 2022 [3 favorites]

I feel like one could get the same effect with an array of smaller emitters in parabolic reflectors which would solve the size problem, the heat problem, the extremely custom build a.k.a. over engineering problem, etc ... and if one were not anal-retentive about the rays being entirely parallel, one could do it mostly parallel with an array of off-the-shelf led spotlighting bulbs which would still be highly directional if not producing the same sharp shadows; but if you're going to put a diffuser in front of it anyway, it doesn't matter that much.
posted by seanmpuckett at 7:57 AM on September 8, 2022

Internet:  Look at this fun and [somewhat] easy DIY project!
MetaFilter:  LIfe is but a parade towards death.


Oh MetaFilter, never change!
posted by los pantalones del muerte at 8:14 AM on September 8, 2022 [25 favorites]

Nah seanmpuckett, unless the smaller LEDs are more efficient the heat would be the same, then you would have to have to build N reflectors and have N heat-sinks, and have N points of failure. And it's not a diffuser, it's a selective frequency filter/diffuser that brings the Sun's black body emission spectrum down to match what happens here on the surface of the planet naturally. The single source also at a glance out the window does look like an infinite-ish distant source. Now they just need to put it on a rotate/tilt controller do that the 'sunlight' travels across the room in a natural manner.

Anyways, in the cold sunless places... the heat is probably good. Point those radiators into the room so it's also both sunny and warm.

Build a sun coming in the window. Not just spherical cow sunlight replacement.
posted by zengargoyle at 8:18 AM on September 8, 2022 [1 favorite]

I loved the video, thank you!

For those without seasonal depression, know that the northern thirst for sunlight on about February is intense, and I would totally build this three times over if it would help.

Also, the cute SAD initialism was a horrible idea. Even medical professionals trivialize it.

If anyone needs me, I'll be out in the garden, dreading the fall.
posted by SunSnork at 8:22 AM on September 8, 2022 [4 favorites]

(I should clarify: I'm not complaining about the title using the SAD acronym, it's fine! I just wish the medical establishment had a better term.)
posted by SunSnork at 8:35 AM on September 8, 2022 [1 favorite]

spherical cow sunlight replacement

My next sockpuppet name!
posted by Greg_Ace at 8:42 AM on September 8, 2022 [2 favorites]

I love this and need this but was sad to see the amount of space it takes up, impossible with where I am living. Otherwise I'd be building myself an artificial sky light right now.

I do hope someone builds on it and makes it more compact. Until then, I may have to build one of these by the same youtuber.
posted by [insert clever name here] at 8:56 AM on September 8, 2022 [2 favorites]

I feel like one could get the same effect with an array of smaller emitters in parabolic reflectors which would solve the size problem, the heat problem, the extremely custom build a.k.a. over engineering problem, etc ... and if one were not anal-retentive about the rays being entirely parallel

The shadows are basically the outline of e.g., your hand convolved by the light source (see shadows during a partial solar eclipse), and you would sure as heck see in the shadows that you had a grid of lights rather than a single light source. There are streetlights that basically have a grid of focused LEDs, and they make absolutely awful shadows. I don't think this would look much like sunlight in terms of shadows and I think it would look less like sunlight if you looked at it.

That said, if you're only concerned about SAD purposes, probably none of this matters and just a big light with a lot of output with a good spectrum that you put anywhere in the room with any focus would do a pretty good job.
posted by aubilenon at 9:11 AM on September 8, 2022 [1 favorite]

> I feel like one could get the same effect with an array of smaller emitters

If you watch with captions on you'll see exactly this suggestion at the end of the video

> unless the smaller LEDs are more efficient the heat would be the same,
> then you would have to have to build N reflectors and have N heat-sinks

Well the heat sources are spread across the whole area instead of being all at one point so you could probably just convect it away with a sensible design, which makes it easer to effectively...

> Point those radiators into the room so it's also both sunny and warm

Definitely a good idea - this is using a lot of power for just a light source.

I think I want one.
posted by merlynkline at 9:50 AM on September 8, 2022

> There are streetlights that basically have a grid of focused LEDs, and they make absolutely awful shadows

Those are not collimating parallel rays - that would pretty much solve that problem.
posted by merlynkline at 9:53 AM on September 8, 2022

He did a different version of it about a year before this one, using the diffuser of (trashed) tvs , not sure if the brightness is enough to combat SAD, but takes up less space than the one above and also mimics sunlight's collimation.
posted by defcom1 at 11:16 AM on September 8, 2022 [1 favorite]

This seemed like it would be great for a basement apartment until the part where you need an entire separate room to house the parabolic dish assembly. Cool effect, though.
posted by rodlymight at 1:26 PM on September 8, 2022

He left out the part about dedicating an entire closet or small room for the reflector assembly. It’s cool and all, but it’s also easily its own sendup of DIY nerds.
posted by Thorzdad at 3:02 PM on September 8, 2022 [1 favorite]

He left out the part about dedicating an entire closet or small room for the reflector assembly.

He left that out of what? The video makes that pretty clear.
posted by aubilenon at 3:44 PM on September 8, 2022 [1 favorite]

Just got around to watching this, and wow this is great. Amazing attention to detail. I do wonder if a smaller version that doesn't require as much depth (and thus would be wall-mountable) is doable with a fresnel lens, but I don't understand the optics well enough to really be sure.
posted by wesleyac at 9:29 PM on September 8, 2022

This certainly looks like a fun project and all - but a quick look at the parts list puts this up in the ~£2,000 ballpark.

Meanwhile, I've been buying charity-shop OttLights for ten bucks or so....

It seems like the point of DIY is to build a $2000 Thing for a fraction of the price - and not the other way 'round.
posted by AsYouKnow Bob at 9:59 PM on September 8, 2022

It seems like the point of DIY is to build a $2000 Thing for a fraction of the price - and not the other way 'round.

I think I'd say the point of the kind of DIY that this is is making a thing that's way nicer than anything it's possible to buy. Probably hard to justify the cost if you're just a random person rather than a Youtuber who can use it as a studio light as well, but I can still appreciate it. That's maybe less common than DIYing for cost reasons, but it's definitely a thing that a lot of people appreciate — most of the stuff I have on my list of DIY projects are things that I want just so that I can't buy anywhere, personally.
posted by wesleyac at 10:18 PM on September 8, 2022 [2 favorites]

You could do a fresnel mirror too though, right? With a 3D printer and then fume silver it with aluminum, maybe.

You could also make the reflector so that the LED did not sit in the path of the reflected light.
posted by jamjam at 10:21 PM on September 8, 2022

Reminds me of the artificial skylight that CoeLux introduced a few years ago. It was super expensive and only for commercial installations at the time, but it seems like they do residential projects now.
posted by odin53 at 6:37 AM on September 9, 2022 [1 favorite]