9 HN users recommended this demo8 months2020–2025score 9.5
Years with an HN recommendation, 2007–2026
Whenever HN discusses seasonal affective disorder, myopia, or bright home lighting, people point to this as the most convincing buildable example of sunlight-like illumination.
DIY Perks builds a realistic artificial sun for dark winters, using a powerful water-cooled LED, a satellite dish reflector for near-parallel rays, and a scattering layer to mimic the blue sky. The video explains the optics behind why most lamps do not look like sunlight and shows the build and its results.
“The result is quite stunning. I've never seen anything like it.” (HN, 2022)
There's an amazing youtuber/creator I've been following for a while and he does exactly this. Goes into the science of what it takes, and the results are really stunning. I'd love to give something like this a try, just need time. [this video] Also there was a breakthrough a while ago with LED ceiling lights that mimic natural sun. I haven't heard much since their release, so I'm sure cost is still a major issue for these sadly. [link]
Science of artificial sunlight with stunning results
[this video] If you want one, you can build one following the video above. The result is quite stunning. I've never seen anything like it. [link] The one above is an easier build that takes up less space.
I cannot remember if I first saw this here on HN but, here is a detailed video of an incredible artificial sunlight rig build. It's big but the results look, well, amazingly real, at least to the camera. [this video]
Detailed build of an incredibly realistic artificial sunlight rig
This isn't quite what you're looking for, but this has some of what you're looking for, which is how to get the "parallel light effect" that the sun has, so it doesn't look like a bulb, and diffuses properly: [this video] Hope this helps a little.
Shows how to get the parallel light effect of the sun
Relevant YouTube video with 2M views: “Building an artificial sun that looks unbelievably realistic …” [this video] [link] Uses a water cooled LED lamp reflected off a satellite dish to produce parallelised rays and through a soapy filter to provide diffuse light. Bulky, but literally lights a room as if from a morning sun on a spring day.
Water-cooled LED and satellite dish making realistic morning sun
I'd wager they're pretty good. If you can leverage a parabolic reflector at a light's focal length, you can get them to collimate in a way that approximates the sun by appearing to be pinned near-infinitely far away. The reflector is generally what takes up the space, but it's necessary(ish) -- you could approximate the effect by using a fresnel lens at the light's focal length, but it yields a smaller light with rainbowing effects. [This video]( [this video] ) does a good job of showing how to make your own, as well as illustrating how good the effect is, while also demonstrating why space-hog implementations are likely to yield good results and slimmer ones not.
Shows making your own collimated sunlight and how good the effect is
DIY Perks also attempted to make artificial sunlight at home, also focusing on things like Rayleigh scattering! This was a great watch: [this video] EDIT: After reading the article, I see the OP calls out DIY Perks specifically - the OPs design is much more compact :) > It's compact. The total size is 19cm x 19cm x 9cm. This is quite compact for a 5cm focal length and an effective lighting area of 18cm x 18cm. Reflective designs like the DIYPerks video or commercial products like CoeLux do not achieve this form factor.
Artificial sunlight at home featuring Rayleigh scattering
Think operating room or photo studio. 100w grow light panel for every 2-3 square meters - so for a typical office, 4 100w lights, with a scatter panel in front. I really like this video for an example of how to make proper scattering effect, but you can buy similar materials that are more durable and lighter, for in e.g. a drop ceiling: [this video]
You might be interested in this video too. There’s more to it than just the color, sunlight’s rays are (virtually) parallel, because the light source is so far away. [this video]
I was going to suggest diy perks but thought you were going to link his artificial sun video [1]. I’ve been wanting to build one but not sure where I could fit since it requires a bit more space then a bright led build would. [this video]
Definitely not quicker and easier, but artificial sunlight (like this [this video] ) has impressed me and wondering if there are ready made solution for that
> satellite dish, silvered, with an LED array at the focal point An example from DIY Perks YouTube channel [0]. [0] Building an artificial sun that looks unbelievably realistic. [this video]
This reminded me of the video by DIY Perks building an "artificial sunlight" for their office: [this video] The amount of effort is unbelievable, but I'd love to have something like this at home. I can only imagine the impact on my productivity during winter evenings…
I really wish more led lighting was high CRI. We've suffered a huge degredation to our world vua this switch to efficiency & it's sad & unknown. Boo. These Yuji led folk notably appear in the DIY Perks videos on indoor sunlight! He uses a 500W watercooled setup & adapted parabolic satellite dish reflector in the second to make good parallel-rays sunlight. [link] [this video]
500W water-cooled setup with parabolic reflector for parallel-ray sunlight
I don't have SAD(at least to a degree I notice), but I do occasionally daydream of having something like this artificial sunlight in my windowless office at work. If only I had more space. [this video]
Daydream of artificial sunlight in a windowless office
This is a rabbit hole :) In short, no, unless you have tens-of-thousands[1][2] to spend on this panel. Rays of sunlight are parallel, an effect that very difficult to emulate. There are folks who have developed DIY versions, with impressive results[3], but in that case you're trading off way more effort, potentially requiring maintenance, and a lot more space required. [1]: [link] [2]: [link] [3]: [this video]
DIY version with impressive results but heavy effort and space
There are some other implemenations listed on this page. The trick is to make sure the light rays are parallel as if coming from an infinite distance like the sun. To create the blue sky effect the easiest way is to pass the light through soapy water like in this video posted above [this video]
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