My research group used to use a Hollywood spotlight to simulate the lighting in orbit. These lights take a long time to power cycle, so once they're on you kind of want to keep them on, otherwise it's 15-30 minutes once you turn them off before they fully power up again.
So we left it on. After one test we left it pointed at our test article, which was made of styrofoam. After a couple of minutes it started smoking and melting. If we hadn’t smelled the smoke I'm certain it would have caught on fire.
We made very sure we never left it pointed at a fire sprinkler after that.
A school I was working out rented out as a location. The lighting crew followed their standard protocols, power all lights with the generator so when the Location Manager orders the power down they know the lights are off. The wardrobe crew on the other hand decided to move one of the lights for their convenience and plugged it into the building power supply. Someone else had moved a garment rack into range of the light.
About 3am the fire alarm went off. One of the elderly nuns was sleeping in her room on the top level of the building, was carried out by a firefighter.
The school was a converted English Tutor Mansion, had a grand entrance with hand carved mahogany everywhere. The film company hired a crew of like 30 cleaners that were scrubbing the smoke out of the carvings with toothbrushes.
This is why film electricians are very strict about nobody besides them plugging / unplugging anything. The best boy or genny operator is always balancing loads and tracking power usage, especially when house power is in play.
Why is it always the wardrobe department? Years ago I worked as local crew at The Mayflower in Southampton (UK). We had to evacuate during the show one night because wardrobe had a toaster they weren't meant to have, and managed to set fire to some costumes.
I was quite impressed the with the evacuation procedures - almost 3000 people outside in under 3 minutes!
Would you mind specifying which school this was? I'm curious because of your description (presumably that is English Tudor Mansion) of the architecture.
>We made very sure we never left it pointed at a fire sprinkler after that.
The one time we had an inadvertent discharge of a fire sprinkler in the historic building we're in was when a film crew had a light positioned too close to one. It was not close enough that someone without specific experience looking at it would have thought it was too close. The light wasn't even a high-powered outdoor film spotlight; it was for an indoor shoot. Film lights can just be very bright, and very hot.
Since it's that time of year again for my fellow northerners with SAD, film lights can be wonderfully bright, and the heat is a welcome side benefit!
Screw Verilux with their overpriced "10,000 lux" 10W panel (only at less than 6 inches from your face), instead get a high-CRI studio light over my reading chair and I'll be happy all winter.
I worked with a solar simulator that has 19 lamps, each using 35 kW of power. It has a heavy metal shutter that is used to quickly turn off the light. Once the shutter is closed, the operators have ~45 seconds to turn the lamp off, otherwise they risk damaging the shutter.
Some other facts:
* While handling lamps, you are not allowed to be in the lamp room without hearing protection, just in case one implodes.
* A single lamp emits enough light that it can cause permanent blindness.
* Lamps are water-cooled.
(it still lists the old power rating, but it was increased to 35 kW a few years ago, when BepiColombo was tested. The lamps were also refocused at that time, to cover a smaller diameter circle. The sun emits a ridiculous amount of light...)
I wrote the software that monitors lamp output during use, and also the software used to calibrate the alignment of the lamps (they need to be properly centered).
I am absolutely not surprised, this should be a completely expected outcome if you've ever worked with film lights. For reference our light was probably more like 40-50 feet away from our test article.
We loaned it to some NASA colleagues once, but their safety manager refused to allow it in the building. At all.
That article isn't as good (less technical/more 'pop' audience) but they both link the actual AAIB report which I found quite interesting and surprisingly readable, and I don't think either article has anything extra to offer. I'd suggest skipping straight to it:
https://assets.publishing.service.gov.uk/media/6544b3089e05f...
I just don't understand why all movie set lights haven't instantly been replaced by their LED equivalent. Why do people still use these things that are crazy expensive to run and can set things on fire?
Ever heard how painters hunt for pigments? Sure, if you run out of orange you can just mix red and yellow, but the end result will reflect different frequencies than when you used a dedicated orange pigment—meaning some oranges in your final work would look ever so slightly different (and sometimes very different under some light conditions or angles) from other oranges or from what you would like, especially over time.
The situation can also be flipped and apply to light sources, and those by definition are key in photography.
In case of LED light, its colour balance can be declared to match some reference Kelvin number, but because it is “fake”, a mix of spikes in the spectrum (roughly at R, G, and B for RGB LEDs, phosphorus-covered white LEDs have the spectrum more even but its own gaps and bumps), and materials of various colours can reflect inbetween those peaks, or right at those peaks, those materials can look 1) different from scene to scene and from light to light or 2) plain wrong in post production, compounding variance between camera sensors or films (which create colour from their own mix of R, G, and B), lenses, etc.
Added to other flaws of LEDs, such as longevity (of cheaper units), issues with brightness and colour reproduction consistency, PWM, etc., they make a poor choice for a variety of situations[0], but in photography particularly so, particularly where colour reproduction and continuity matter (TV and film).
By contrast, black body radiation—hot and more energy intensive—is a solid spectrum of even light, without spectral discontinuities or flicker at any brightness.
[0] In some situations those flaws are considered acceptable. You may have noticed how two identical OLED iPhones displayed at an Apple Store, even fully reset to defaults, can have obviously different white point when you look at them side by side—that’s colour reproduction/emission variance and/or degradation over time. Similarly, you can often spot PWM flicker if you reduce brightness and squint at an OLED phone with your peripheral vision. These things don’t matter much, since 99.99% of the time we look only at our own device and our colour perception and flicker tolerance is adjusted to it. Not so with photography; you can’t afford colour variance between two different lights even in cases where it’s not noticeable to the naked eye in the moment, whereas PWM restricts your FPS and shutter angle options.
White LEDs do not produce three narrow spectral peaks. That's only RGB LEDs, which are a very specific thing and not the norm.
LED lighting uses phosphors and produces a broad spectrum.
Take a CD / DVD (if you can find one in 2023) and look at the spectrum from your phone flash, or any other LED lamp, and observe the broad spectrum. They all have some sort of blue peak, but it's very small in "warm white" lights.
The cost of running them isn't relevant. What is relevant: being able to get more light from a limited amount of house/set/generator power, and the control over them. They don't require a dimmer pack, just power and DMX (wired or wireless) to control their brightness, color temperature, activate special in-light effects like flickering/strobing, etc.
Some directors prefer the spectrum completeness and profile from tungsten (or the ultimate, carbon-arc, which is virtually indistinguishable from the sun.)
I also think there are levels of light that aren't really feasible except with carbon arc because LEDs don't like heat and that limits power density.
I don't remember what movie it was, but there's a photo of an enormous balloon light - larger than an entire house - over a farmhouse somewhere in the midwest, at night. Pretty sure it wasn't LEDs as the source, but I could be wrong.
Spectrum continuity and spikes, flicker, active cooling, ridiculously short lifespans at ridiculously high levels of brightness, and a sprinkling of “the old way is the only way”?
I've been on a couple of film sets and when those big lights are on you better not be caught unprepared especially not when they are focused. The lights are usually kept running between takes (and during shorter breaks) and you will definitely realize you are 'in the beam' when you walk across the set. Another commenter here mentions UV protection built into make-up, I wasn't aware of that but it makes good sense.
One thing I learned while webcasting Yves St. Laurent's fashion show in the mid 90's is that the flowers wilt within minutes of being placed due to all of the heat from the lights. So the way they dealt with that is that backstage there is an absolutely enormous amount of flowers ready to be deployed and they just cycle through flower arrangements continuously for the duration of the show so that the flowers are always fresh. It's tens of people walking to and fro without pause.
> Loy wrote that the biggest problem during shooting was the climactic dinner party scene in which Nick reveals the killer. Powell complained that he had too many lines to learn and could barely decipher the complicated plot he was unraveling. It was the one scene when several retakes were necessary, which brought up an entirely new problem. The script called for oysters to be served to the dinner guests and, in take after take, the same plate of oysters was brought out under the hot lights. Loy recalled that "they began to putrefy. By the time we finished that scene, nobody ever wanted to see another oyster".
First, stage lighting is already uncomfortably hot for anyone working under them for any length of time.
Second, these weren't ordinary stage lights. These were lights for use outdoors to simulate natural sunlight, which is much brighter (and hotter) than what you'd normally use indoors.
Third, they were probably positioned too close, and left on for too long. Just a guess on this one.
Still, if they are sunlight stimulators, wouldn't that mean that the heat from real sunlight could cause this also? These lights were too far for air heating to be an issue. So it must have been all IR.
Maybe this kind of foam isn't entirely up to the spec either.
There's a minimum distance of like 10-30ft with these lights. They're also uncomfortably warm, prompting humans to leave after a while but not airplanes.
There's that old saying: place a fire under an airplane and it will quickly move itself away. Slowly heat it with film lights and it will stay there until its seals melt. I am surprised the flight crew didn't remember this common saying!
I’ve explained this before but I’ll chime in here and explain it again. Spotlights like these used for filming get hot (temperature wise) as well as having the ability to focus the beam. The lights heat will fall off but a focused beam will retain more of its energy. Now, some movie makeup has built in SPF. Stage makeup definitely has some. On stage, you’ll often see fans blowing to keep people cool or they will use diffused lighting and not spotlights which don’t generate so much heat.
Spotlights like these though, you might as well be holding a giant magnifying glass. The beam is culminated and will cook whatever it’s pointing at. Will it cook a human? Yes if you stand there, still, for long enough. You will definitely get sun burned. If you get within 10 feet it will feel like your standing in an oven. Within 5 feet and your skin could boil.
Overall less energy but locally much more due to the fact that it is focused. By comparison: a lighter doesn't have a whole lot of energy, but it outputs that energy in a tiny volume resulting in combustion. The lights they used are not quite lighters but they can cause fires if you concentrate their output in a small enough area. A tarmac radiating heat is an enormous amount of output but on a W/sqm basis for delivered power it is a fraction of what those lights can do.
So basically, this could have been a serious incident if they used a lower power light that did not cause the window to fail so obviously. I bet with a full pressure differential at cruising alt, this might have blown up catastrophically.
Quite scary what kinds of causes trigger such incidents. As a frequent flier, I would have never imagined something like this.
How are there no regulations that should have prevented or caught this? I bet there will be now.
Aircraft fuselages are not balloons, and they do not catastrophically pop if the fuselage is punctured in discrete locations. Relevant recommended viewing is "operation guillotine fuselage test" on YouTube, where large steel blades are dropped through pressurized aircraft fuselage sections to validate no explosive decompression. In the late 1950s, BTW.
Commercial aircraft are required to be designed to maintain 15,000 foot equivalent cabin altitude after any probable failure, which includes multiple missing windows, per the requirements of 14 CFR 25.841 and it's EASA equivalent.
There is already regulation in place that should have caught this but did not. The captain is required to perform an external visual inspection of the aircraft before departure, which follows a checklist that includes looking at the windows. It appears that did not happen.
> There is already regulation in place that should have caught this but did not. The captain is required to perform an external visual inspection of the aircraft before departure, which follows a checklist that includes looking at the windows. It appears that did not happen.
We've no idea if the damage was visible prior to takeoff. It may have easily passed a visual inspection on the ground before moving at speed with a pressure differential. As per the article at least one of them appears to have detached in flight and struck the horizontal stabilizer.
> How are there no regulations that should have prevented or caught this? I bet there will be now.
I would think a pressure check would be trivial. I would also assume a visual inspection is part of takeoff (camera or human). I assume this sort of thing is rare enough to not warrant the extra time/cost of these trivialities.
Readit News
So we left it on. After one test we left it pointed at our test article, which was made of styrofoam. After a couple of minutes it started smoking and melting. If we hadn’t smelled the smoke I'm certain it would have caught on fire.
We made very sure we never left it pointed at a fire sprinkler after that.
About 3am the fire alarm went off. One of the elderly nuns was sleeping in her room on the top level of the building, was carried out by a firefighter.
The school was a converted English Tutor Mansion, had a grand entrance with hand carved mahogany everywhere. The film company hired a crew of like 30 cleaners that were scrubbing the smoke out of the carvings with toothbrushes.
I was quite impressed the with the evacuation procedures - almost 3000 people outside in under 3 minutes!
The one time we had an inadvertent discharge of a fire sprinkler in the historic building we're in was when a film crew had a light positioned too close to one. It was not close enough that someone without specific experience looking at it would have thought it was too close. The light wasn't even a high-powered outdoor film spotlight; it was for an indoor shoot. Film lights can just be very bright, and very hot.
Screw Verilux with their overpriced "10,000 lux" 10W panel (only at less than 6 inches from your face), instead get a high-CRI studio light over my reading chair and I'll be happy all winter.
Ouch, hopefully the film production company had liability insurance! It’s easy to rack up six figures of damage by setting off fire sprinkler.
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Some other facts:
* While handling lamps, you are not allowed to be in the lamp room without hearing protection, just in case one implodes. * A single lamp emits enough light that it can cause permanent blindness. * Lamps are water-cooled.
Here's a picture of the back of the unit: https://www.esa.int/ESA_Multimedia/Images/2014/04/Sun_simula...
(it still lists the old power rating, but it was increased to 35 kW a few years ago, when BepiColombo was tested. The lamps were also refocused at that time, to cover a smaller diameter circle. The sun emits a ridiculous amount of light...)
Here's a picture of a spacecraft being lit up by the lamps (at a really low light level): https://www.esa.int/ESA_Multimedia/Images/2008/03/GOCE_ready...
I wrote the software that monitors lamp output during use, and also the software used to calibrate the alignment of the lamps (they need to be properly centered).
>I’m really surprised lights used to simulate sunrise placed 20-30ft away could completely melt the foam holding the exterior windows in place.
https://news.ycombinator.com/item?id=38221699
We loaned it to some NASA colleagues once, but their safety manager refused to allow it in the building. At all.
styrofoam melts super easily so not sure that says much
It was a brand new arc lamp.
That article isn't as good (less technical/more 'pop' audience) but they both link the actual AAIB report which I found quite interesting and surprisingly readable, and I don't think either article has anything extra to offer. I'd suggest skipping straight to it: https://assets.publishing.service.gov.uk/media/6544b3089e05f...
The situation can also be flipped and apply to light sources, and those by definition are key in photography.
In case of LED light, its colour balance can be declared to match some reference Kelvin number, but because it is “fake”, a mix of spikes in the spectrum (roughly at R, G, and B for RGB LEDs, phosphorus-covered white LEDs have the spectrum more even but its own gaps and bumps), and materials of various colours can reflect inbetween those peaks, or right at those peaks, those materials can look 1) different from scene to scene and from light to light or 2) plain wrong in post production, compounding variance between camera sensors or films (which create colour from their own mix of R, G, and B), lenses, etc.
Added to other flaws of LEDs, such as longevity (of cheaper units), issues with brightness and colour reproduction consistency, PWM, etc., they make a poor choice for a variety of situations[0], but in photography particularly so, particularly where colour reproduction and continuity matter (TV and film).
By contrast, black body radiation—hot and more energy intensive—is a solid spectrum of even light, without spectral discontinuities or flicker at any brightness.
[0] In some situations those flaws are considered acceptable. You may have noticed how two identical OLED iPhones displayed at an Apple Store, even fully reset to defaults, can have obviously different white point when you look at them side by side—that’s colour reproduction/emission variance and/or degradation over time. Similarly, you can often spot PWM flicker if you reduce brightness and squint at an OLED phone with your peripheral vision. These things don’t matter much, since 99.99% of the time we look only at our own device and our colour perception and flicker tolerance is adjusted to it. Not so with photography; you can’t afford colour variance between two different lights even in cases where it’s not noticeable to the naked eye in the moment, whereas PWM restricts your FPS and shutter angle options.
Take a CD / DVD (if you can find one in 2023) and look at the spectrum from your phone flash, or any other LED lamp, and observe the broad spectrum. They all have some sort of blue peak, but it's very small in "warm white" lights.
Some directors prefer the spectrum completeness and profile from tungsten (or the ultimate, carbon-arc, which is virtually indistinguishable from the sun.)
I also think there are levels of light that aren't really feasible except with carbon arc because LEDs don't like heat and that limits power density.
I don't remember what movie it was, but there's a photo of an enormous balloon light - larger than an entire house - over a farmhouse somewhere in the midwest, at night. Pretty sure it wasn't LEDs as the source, but I could be wrong.
Not a balloon, but a big diffuser with a whole bunch of Cineo 410 LED sources.
Deleted Comment
[0]: https://news.ycombinator.com/item?id=38221121
One thing I learned while webcasting Yves St. Laurent's fashion show in the mid 90's is that the flowers wilt within minutes of being placed due to all of the heat from the lights. So the way they dealt with that is that backstage there is an absolutely enormous amount of flowers ready to be deployed and they just cycle through flower arrangements continuously for the duration of the show so that the flowers are always fresh. It's tens of people walking to and fro without pause.
https://en.wikipedia.org/wiki/The_Thin_Man_(film)#Filming
(Great movie BTW!)
Second, these weren't ordinary stage lights. These were lights for use outdoors to simulate natural sunlight, which is much brighter (and hotter) than what you'd normally use indoors.
Third, they were probably positioned too close, and left on for too long. Just a guess on this one.
Maybe this kind of foam isn't entirely up to the spec either.
Spotlights like these though, you might as well be holding a giant magnifying glass. The beam is culminated and will cook whatever it’s pointing at. Will it cook a human? Yes if you stand there, still, for long enough. You will definitely get sun burned. If you get within 10 feet it will feel like your standing in an oven. Within 5 feet and your skin could boil.
The reasoning was that:
- college students are busy/forgetful so will leave the light on
- there are times of day where no one would be in a dorm room
- BUT that dorm room is a bigger dorm with potentially lots of other students
- an unattended halogen lamp could set fire to an object on a desk etc
this post feels like a much bigger version of the above
Quite scary what kinds of causes trigger such incidents. As a frequent flier, I would have never imagined something like this.
How are there no regulations that should have prevented or caught this? I bet there will be now.
Commercial aircraft are required to be designed to maintain 15,000 foot equivalent cabin altitude after any probable failure, which includes multiple missing windows, per the requirements of 14 CFR 25.841 and it's EASA equivalent.
There is already regulation in place that should have caught this but did not. The captain is required to perform an external visual inspection of the aircraft before departure, which follows a checklist that includes looking at the windows. It appears that did not happen.
We've no idea if the damage was visible prior to takeoff. It may have easily passed a visual inspection on the ground before moving at speed with a pressure differential. As per the article at least one of them appears to have detached in flight and struck the horizontal stabilizer.
Also the engineer who signed off the aircraft will do a walk around.
The location of these windows might have made it hard to spot the damage.
I would think a pressure check would be trivial. I would also assume a visual inspection is part of takeoff (camera or human). I assume this sort of thing is rare enough to not warrant the extra time/cost of these trivialities.