Building a realistic artificial sun (for dark winter days)

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

▶ 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.

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

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

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.

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.

This guy also showed how to make an "artificial sun" that's proven very helpful to me in Oregon winters: ▶ this video

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.

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.

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

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

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