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by VohuMana 948 days ago
I’m really surprised lights used to simulate sunrise placed 20-30ft away could completely melt the foam holding the exterior windows in place.
2 comments

I was doing slomo capture of objects being dropped into a small fish tank. I only had a small lighting kit where my largest light was only 750w. To compensate, I placed the lamps mere inches away. By the end of the shoot, the heat melted the top frame of the tank that would normally hold the housing for the tank's light.

Some productions can bring out 10K lamps and larger. They definitely get H O T.

Only 750W?

That's as much heat as some electric stovetops produce.

Yeah, 1K, 2K, 5K, 10K are all available lighting options. Really, anything less than 1K, and people would look at you with that "ahh, isn't that cute" for bringing out your Fisher Price Baby's First Light Kit. At least that's what one gaffer told me he called the kits from Lowel that had 500W, 750W, and the big light was 1K. Before LEDs and fluorescent lighting, "hot" lights had that moniker for a reason. Having stuff ruined because of the heat of a light source was not a rare event, especially for noob gaffer/grip types.
That's about just under two RTX 4080 Tis, measured in techie units that you might be more familiar with.
Isn't that just half a hair dryer? Is it for keeping things warm?
Well, my biggest light might have only been 750w, but I had three of them running. So, a decent space heater. Only these are more useful, as the heat was generated but also made all of that wonderful light.
I guess I can imagine a grownup Easy Bake Oven with those.
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Oh I don't know. The aircraft appears to be painted with a dark colored paint; that would naturally absorb any heat energy from the lights, and film set lights are really bright.
Yes, but what about the same place, sitting on the tarmac in hot latitude airport (Singapore, Doha, Las Vegas, etc.) ? It is a bit puzzling to know that heat from lights could damage windows of an airplane.
Cribbing off [another comment](https://news.ycombinator.com/item?id=38222198), there's as much as 72kW of lighting being focused on a few square meters of the plane's skin. Direct sunlight at noon at the equator is roughly 1kW/m²; the artificial lighting here is well over an order of magnitude brighter than the sun.
the sun is very very hot and bright, but it is also very far away.
Inverse square law should apply to the lights too. The lights may be bright and very hot but each meter away from them would mean a significant drop in the transmitted energy.
Inverse square applies to spherically projected energy. It was directed in this case.
No
Stage lights can reach 90c.
Why don't they bake the actors then?
SPF 200. Also the heat will dissipate over distance. At a rock concert where the ambient temperature is 32c due to being packed with humans, the heat can’t dissipate at well and so you get 60c on stage. Melt cables. Input jacks. Doc Martin soles.

You’ll often see those giant fans blowing all over the stage. It’s not just for big hair stances, it’s to keep humans alive.

On sets, less humans, more space, so the lights heat will dissipate pretty well after 5-10 feet. However I suspect that a simulator that is simulating the sun using a physical lamp would be using higher power lights to mimic the suns bloom. Even keeping it within operating normals it will get hot.