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I tried making artificial sunlight at home

victorpoughon.fr

171–180 of 243 posts

Re: I tried making artificial sunlight at home

#171
post #39

Really cool! I'm working on a lamp that gives you daylight levels of light indoors (albeit no raleigh scattering and columnated light). On the bright side (pun intended), it's 50,000 lumens instead of ~4500. https://getbrighter.com/

Had the chance to see one of these in person - did not believe you could achieve “daylight indoors” before I did.

I have a 200W LED flood light and it was the most depressing thing to shine indoors. EVERYTHING was covered in dust and filth that you wouldn't see under normal-intensity light. It felt like things had collapsed and I was surveying the remains of someone's house.

Re: I tried making artificial sunlight at home

#173
post #164

Earlier quoted context omitted.

Do you have any insight on how to take spectroscopy measurements at home on a <1k€ budget? And how to select an LED manufacturing supplier when CRI is often the only thing available on the datasheet?

A little garden spectrometer is pretty good, and around $60: https://www.youtube.com/watch?v=LxQmaJYMOAk . And the LED supplier should give a spectrometer graph. If you can get a dual peak LED that will give a better spectrum distribution. The Amaran 200x S is one of the best.

Very cool! I definitely want a spectrometer at home now! edit: looks like it's more of a DIY project than a commercial thing. Maybe DIY spectrometer is my next project then!

Re: I tried making artificial sunlight at home

#175

Very cool. I’m the CEO of Innerscene ( https://innerscene.com ) and we make a commercial artificial skylight that uses some of these concepts. Actually the coelux ht25 model is almost identical to what you made but using smaller lenses and more LEDs - however the effect they were able to achieve still isn’t that great, the sun looks like a giant orb and once you get a few feet away you can make out a sun at all. We s…

Totally makes sense that things like seamless edge blending and fine-tuned collimation end up being the biggest challenges

Re: I tried making artificial sunlight at home

#176

For me, the problem with this setup (and with most high efficiency LED lights) is the lack of red wavelenghts. Real sunlight has a substantial amount of energy in the very red end of the visible spectrum (700 nm) and also of course quite a bit in the infrared. These lamps have two spectral peaks: a narrow peak in the blue range, around 450 nm, a broader peak in the green, centered around 580 nm. That greenish peak fa…

That's a really interesting point, and one I hadn't considered in depth...

Re: I tried making artificial sunlight at home

#177
I’ve been thinking about the potential benefits of incorporating something like this into VR headsets. Since VR already controls the user’s visual perception, would adding a high-intensity blue light (not via the OLED displays but indirectly) allow for a more effective way to simulate bright daylight conditions? Achieving 10,000 lux at the eye would be much easier this way.

Re: I tried making artificial sunlight at home

#178

Cool, but you can get brightness enhancement film for very cheap in AliExpress: https://www.aliexpress.com/i/2255799825024246.html The brightness enhancement film is a transparent optical film. It consists of a three-layer structure. The bottom layer of the light-incident surface needs to provide a certain degree of haze by back coating, the middle layer is a transparent PET substrate layer, and the upper layer of li…

I wasn't aware this existed, thanks! Very interesting.

Re: I tried making artificial sunlight at home

#179

Earlier quoted context omitted.

What you want is at odds with energy efficiency and is therefore being made illegal https://blog.medcram.com/uncategorized/new-department-of-ene...

Again, another regulatory decision that makes a niche worse off overall.... Abuses of a carve-out aside, having a "Sunlight mimicking" exemption would solve this, with the added conditions that they have to actually stick to the EMF outputs of the sun to get this approval. The article itself does this with “General Wellness Lamps”. Otherwise, the only non-reg way to solve this would be to find infrared & red LEDs and…

I mean, wouldn't an IR carbon filament heater suffice? Probably a bit longer wavelengths, but you can still see it glow, so you're getting at least a bit close to the visible spectrum

Re: I tried making artificial sunlight at home

#180
There already exists a fairly good replica of sunlight, Philips CDM. I used it when I was growing weed, lushest bushes I’ve ever seen. 10/10 buds.

It was discontinued for a while but I’m happy to see it’s back in production?

https://www.futuregarden.co.uk/philips-ceramic-discharge-met...

I would pick a CDM bulb any day over the alternatives, including LED, unless power consumption is an issue.

“ Philips daylight CDM lamps are extremely efficient ceramic metal halide lamps with a spectral output close to natural sunlight. As a result, plants form more lateral branches, have smaller inter-nodal spacing, more flowering sites, and larger root systems, culminating in strong, healthy growth and high-quality yields.

Philips CDM bulbs have an amazing operating life. They maintain their high output for a lifespan of 30,000hrs on average.”

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