Okay, first off I feel the obligation to say a few words on the nature of a sci-fi convention. YES, it is an incredibly geeky endeavor, many of the stereotypes are pretty much entirely accurate. But still it isn't necessarily what you picture when you hear the term "science fiction convention". There are many types, the "world con" style is the type that's probably most well known. I'm not really into that style, I've never been to one and wouldn't really go out of my way to see one. Too much blatant commercialism for my liking, although the idea of the spectacle does intrigue me.
I guess I might as well provide a link, it's a local event that's been happening in a hotel close to where I live for quite a while, but I'd never gone before this year. It's called Duckon, the name is derived from the county it takes place in, Dupage. Events like this are more like a weekend long party that takes over a hotel with science fiction overtones. Yes, there are some costumes, but not as many as you might expect. The guests of honor aren't so much famous actors as literary figures and artists. It's a much less formal affair, you can hang out with your fellow geeks, they had two different rooms rigged up to show movies, one handled basic science fiction and the other handled Japanese animation, and there was a lot of other activities, mostly presentations or discussions known as panels. It kind of felt like my time on the Disney cruise line, because of the way that I had a list of the scheduled activities and had to figure out which ones I wanted to catch.
I had a great time. I didn't get to do near as much as I wanted, there was too much going on at once and I basically completely missed out on the last day due to unpleasant after effects of the previous night's partying combined with a rather nasty and lingering virus that I picked up at some point, the partying probably weakened my system enough that the virus had free reign to do a little partying of its own.
But anyway, pictures. I didn't exactly plan this, but most of the pictures I took are of things you either can or used to be able to see at Disney World. I mean beyond things like obsessive fans wearing novelty t-shirts that declare their genre loyalty of choice. A lot of the convention wasn't exactly photogenic, a bunch of people sitting in a room listening to a guy tell odd and sometimes disturbing stories about his scientific career doesn't make for great pictures. There are really two main things I shot, and I'll start things off with a "can you guess what you're looking at" sort of thing. Unless you've not only seen this sort of thing in person but also photographed it you're not likely to recognize it though, it's a rather particular phenomenon.
[attachment=1]
[attachment=2]
So, any guesses?
It's a closeup of the electricity arcing off of a Tesla coil. One of a pair of units designed with the unusual ability to play music. They're known as the singing Tesla coils, and can be seen on youtube.
one from last year
a song from this year
I'm fascinated by the repeating pattern effect you get when you take a picture of them. It's kind of like my experience shooting auroras, what you see on the image looks very different from what you experience in person. Unless you use a very short exposure, then you see what is basically happening in real time. The reason for the pattern is based on how the coils operate. The make the musical tones by pulsing, sending a short burst of electricity and then cutting off the juice and then sending another burst out, I think they basically send as many pulses as the frequency of the sound they want to create. So 1,000 pulses per second for a 1 kilohertz tone, and so on. But that's a guess, I'm not entirely clear how they do it. So what happens is, to start off the pattern you get a single zap that creates a pathway of ionized air. The next zap will want to follow that same path because it offers less resistance than the surrounding air. But the air is moving, this is outdoors and the wind was blowing. So what happens is you get one arc that creates a pathway, then the pathway moves and the next zap still follows the pathway, now displaced by the wind. Eventually the pathway has moved too far and the electricity makes a new path instead and the process starts over. A long exposure creates a complex web-like pattern composed of multiple sets of paths, some terminating in the air, some reaching the ground. It may be that the air is also heated, so even if the air were still the pathways might at least rise from convection.
However the long exposures make the image look rather messy, somehow the effect is lost. So here's a more moderate exposure:
[attachment=3]
I really like the guys that put on this show. They're showmen. They start off with some music (which doesn't sound great, let's just be honest, it's a cool effect but the waveform created by the electricity is fairly crude and harsh) and keep the audience entertained with that for a while, and then once we'd been warmed up this crazy guy in what is referred to as a personal Faraday cage (a Faraday cage is a metal enclosure designed to protect the area inside the cage from radio waves, Tesla coils are said to emit RF frequency electricity so the same principle seems to apply) but which is basically looks like a chain mail suit plus a chicken wire helmet.
[attachment=4]
He is holding fluorescent tubes, which can be illuminated by the Tesla coils even if no electricity directly strikes them. Notice the colored tubes sticking out of the ground? There's no direct strikes in that image, they glow whenever the coils are energized. That was the big excitement about Tesla coils, the ability to transmit high frequency electricity through the air, wireless power distribution.
Next notice this guy's feet. The suit includes stilt-like arrangements attached to the bottom of rubber boots. It emphasizes that the current is really running through (or more accurately over, high frequency electricity follows the surface of a conductor) his suit, it's not just protecting him, it's a conductor that the electricity uses to make its way to the ground. While you can't see it running across the metal you can sure see it when it jumps from his soles to the ground. This guy is walking around intentionally getting the electricity to strike his suit (including the helmet) and looking like some sort of comic book super villain as the electricity arcs off his feet onto the ground.
Video of the suit in action, not taken at the convention
The three people behind this display, the two that built it and the one that wears the suit, gave a talk during the day of the convention that I attended. I wish I could remember how much power they said it consumed, it was a lot. They specified that they powered it using two independent 240 volt high current power lines intended to be used for stage lighting in the hotel. Even with that much power they still have to control how much power it consumes, the higher frequency sounds tend to consume more because they require more pulses. But their control system is fancy enough that they can control how much power each pulse gets, they throttle back the power available to the high frequency stuff to keep the power usage in check.
From the talk I know that, despite that kind of power being directed onto the suit, it never even warms up. I guess it must be an efficient enough conductor that it doesn't generate too much resistance.
I also know that, curiously enough, the control mechanism that allows them to control the individual pulses (something traditional Tesla coils lack, they use a spark gap that lets the coil build up to a certain voltage and then discharge) uses hardware made to run electric locomotives. It's a special type of transistor that can handle extremely high loads. To keep costs in check they buy these things second hand, after they've already been used in locomotives. A laptop controls the whole arrangement and sends control signals over fiber optic wire (presumably to avoid using a long stretch of metal wire that could have an electric current induced in it from the magnetic field being put out by the Tesla coils) which is covered in metal mesh shielding that protects it from direct strikes.
To demonstrate the destructive potential of the electricity, Terry (chain mail suit guy) held up a number of CDs to the output from one of the coils. This didn't photograph well, but the electricity basically ate away at the CD. Either it would end up disintegrating in his hands or after a while he'd walk to the edge of the safety barrier and hand the remnant of the disc to someone in the crowd. He had been using what looked like a glass shield to demonstrate the insulating properties of glass, but it didn't work right and the entire shield shattered. After a few more antics they shut down the show to have people go in and sweep up the mess. Yes, that's right, after demonstrating that the coils could shatter a glass shield they walked in and swept up. I noticed that the control hardware for the coils included a safety key, after they discharged the coils (they accumulate and store power, you have to discharge them to really make them safe) the key would be pulled and presumably the whole thing was safe.
Now then, I said that this has something to do with Disney World. I don't know if anyone remembers or even saw this, but one year when I was at The World they had a night show at Epcot, it took place in a stage south of the big fountain. It was Tesla coil oriented, the people on stage with the coils called themselves the "shock jocks" and they did some things to demonstrate the unique nature of Tesla coils, including of course the ability to transmit electricity through the air to power things wirelessly. It was a pretty slick show, my only complaint was that, as is too often the case, the PA system they used to broadcast their voices was LOUD and the woman leading the whole thing had a kind of shrill voice that just bored straight into my skull. I remember the intense pain that accompanied her declaring "we're the shock jocks!". Still it was a fun show, a nice blending of science based education and entertainment, the sort of thing that is theoretically the domain of Epcot.
The singing Tesla coils weren't exactly quiet, but I'd known to expect that from the comments on the youtube videos. I brought earplugs to the show at Duckon and listened in comparative comfort.
I'll end my tales for now, I tried but completely failed to keep the size of this post in check. I can't help it, the whole Tesla coil thing is geek overload for me. The other main comparison between the convention and Disney World involves a certain species of animal, other than human, that can be found at both places. And I'm talking about a real animal, not something like a Wookie (although I did see one of those too). I've got to edit down those pictures first though.
[This attachment has been purged. Older attachments are purged from time to time to conserve disk space. Please feel free to repost your image.]
I guess I might as well provide a link, it's a local event that's been happening in a hotel close to where I live for quite a while, but I'd never gone before this year. It's called Duckon, the name is derived from the county it takes place in, Dupage. Events like this are more like a weekend long party that takes over a hotel with science fiction overtones. Yes, there are some costumes, but not as many as you might expect. The guests of honor aren't so much famous actors as literary figures and artists. It's a much less formal affair, you can hang out with your fellow geeks, they had two different rooms rigged up to show movies, one handled basic science fiction and the other handled Japanese animation, and there was a lot of other activities, mostly presentations or discussions known as panels. It kind of felt like my time on the Disney cruise line, because of the way that I had a list of the scheduled activities and had to figure out which ones I wanted to catch.
I had a great time. I didn't get to do near as much as I wanted, there was too much going on at once and I basically completely missed out on the last day due to unpleasant after effects of the previous night's partying combined with a rather nasty and lingering virus that I picked up at some point, the partying probably weakened my system enough that the virus had free reign to do a little partying of its own.
But anyway, pictures. I didn't exactly plan this, but most of the pictures I took are of things you either can or used to be able to see at Disney World. I mean beyond things like obsessive fans wearing novelty t-shirts that declare their genre loyalty of choice. A lot of the convention wasn't exactly photogenic, a bunch of people sitting in a room listening to a guy tell odd and sometimes disturbing stories about his scientific career doesn't make for great pictures. There are really two main things I shot, and I'll start things off with a "can you guess what you're looking at" sort of thing. Unless you've not only seen this sort of thing in person but also photographed it you're not likely to recognize it though, it's a rather particular phenomenon.
[attachment=1]
[attachment=2]
So, any guesses?
It's a closeup of the electricity arcing off of a Tesla coil. One of a pair of units designed with the unusual ability to play music. They're known as the singing Tesla coils, and can be seen on youtube.
one from last year
a song from this year
I'm fascinated by the repeating pattern effect you get when you take a picture of them. It's kind of like my experience shooting auroras, what you see on the image looks very different from what you experience in person. Unless you use a very short exposure, then you see what is basically happening in real time. The reason for the pattern is based on how the coils operate. The make the musical tones by pulsing, sending a short burst of electricity and then cutting off the juice and then sending another burst out, I think they basically send as many pulses as the frequency of the sound they want to create. So 1,000 pulses per second for a 1 kilohertz tone, and so on. But that's a guess, I'm not entirely clear how they do it. So what happens is, to start off the pattern you get a single zap that creates a pathway of ionized air. The next zap will want to follow that same path because it offers less resistance than the surrounding air. But the air is moving, this is outdoors and the wind was blowing. So what happens is you get one arc that creates a pathway, then the pathway moves and the next zap still follows the pathway, now displaced by the wind. Eventually the pathway has moved too far and the electricity makes a new path instead and the process starts over. A long exposure creates a complex web-like pattern composed of multiple sets of paths, some terminating in the air, some reaching the ground. It may be that the air is also heated, so even if the air were still the pathways might at least rise from convection.
However the long exposures make the image look rather messy, somehow the effect is lost. So here's a more moderate exposure:
[attachment=3]
I really like the guys that put on this show. They're showmen. They start off with some music (which doesn't sound great, let's just be honest, it's a cool effect but the waveform created by the electricity is fairly crude and harsh) and keep the audience entertained with that for a while, and then once we'd been warmed up this crazy guy in what is referred to as a personal Faraday cage (a Faraday cage is a metal enclosure designed to protect the area inside the cage from radio waves, Tesla coils are said to emit RF frequency electricity so the same principle seems to apply) but which is basically looks like a chain mail suit plus a chicken wire helmet.
[attachment=4]
He is holding fluorescent tubes, which can be illuminated by the Tesla coils even if no electricity directly strikes them. Notice the colored tubes sticking out of the ground? There's no direct strikes in that image, they glow whenever the coils are energized. That was the big excitement about Tesla coils, the ability to transmit high frequency electricity through the air, wireless power distribution.
Next notice this guy's feet. The suit includes stilt-like arrangements attached to the bottom of rubber boots. It emphasizes that the current is really running through (or more accurately over, high frequency electricity follows the surface of a conductor) his suit, it's not just protecting him, it's a conductor that the electricity uses to make its way to the ground. While you can't see it running across the metal you can sure see it when it jumps from his soles to the ground. This guy is walking around intentionally getting the electricity to strike his suit (including the helmet) and looking like some sort of comic book super villain as the electricity arcs off his feet onto the ground.
Video of the suit in action, not taken at the convention
The three people behind this display, the two that built it and the one that wears the suit, gave a talk during the day of the convention that I attended. I wish I could remember how much power they said it consumed, it was a lot. They specified that they powered it using two independent 240 volt high current power lines intended to be used for stage lighting in the hotel. Even with that much power they still have to control how much power it consumes, the higher frequency sounds tend to consume more because they require more pulses. But their control system is fancy enough that they can control how much power each pulse gets, they throttle back the power available to the high frequency stuff to keep the power usage in check.
From the talk I know that, despite that kind of power being directed onto the suit, it never even warms up. I guess it must be an efficient enough conductor that it doesn't generate too much resistance.
I also know that, curiously enough, the control mechanism that allows them to control the individual pulses (something traditional Tesla coils lack, they use a spark gap that lets the coil build up to a certain voltage and then discharge) uses hardware made to run electric locomotives. It's a special type of transistor that can handle extremely high loads. To keep costs in check they buy these things second hand, after they've already been used in locomotives. A laptop controls the whole arrangement and sends control signals over fiber optic wire (presumably to avoid using a long stretch of metal wire that could have an electric current induced in it from the magnetic field being put out by the Tesla coils) which is covered in metal mesh shielding that protects it from direct strikes.
To demonstrate the destructive potential of the electricity, Terry (chain mail suit guy) held up a number of CDs to the output from one of the coils. This didn't photograph well, but the electricity basically ate away at the CD. Either it would end up disintegrating in his hands or after a while he'd walk to the edge of the safety barrier and hand the remnant of the disc to someone in the crowd. He had been using what looked like a glass shield to demonstrate the insulating properties of glass, but it didn't work right and the entire shield shattered. After a few more antics they shut down the show to have people go in and sweep up the mess. Yes, that's right, after demonstrating that the coils could shatter a glass shield they walked in and swept up. I noticed that the control hardware for the coils included a safety key, after they discharged the coils (they accumulate and store power, you have to discharge them to really make them safe) the key would be pulled and presumably the whole thing was safe.
Now then, I said that this has something to do with Disney World. I don't know if anyone remembers or even saw this, but one year when I was at The World they had a night show at Epcot, it took place in a stage south of the big fountain. It was Tesla coil oriented, the people on stage with the coils called themselves the "shock jocks" and they did some things to demonstrate the unique nature of Tesla coils, including of course the ability to transmit electricity through the air to power things wirelessly. It was a pretty slick show, my only complaint was that, as is too often the case, the PA system they used to broadcast their voices was LOUD and the woman leading the whole thing had a kind of shrill voice that just bored straight into my skull. I remember the intense pain that accompanied her declaring "we're the shock jocks!". Still it was a fun show, a nice blending of science based education and entertainment, the sort of thing that is theoretically the domain of Epcot.
The singing Tesla coils weren't exactly quiet, but I'd known to expect that from the comments on the youtube videos. I brought earplugs to the show at Duckon and listened in comparative comfort.
I'll end my tales for now, I tried but completely failed to keep the size of this post in check. I can't help it, the whole Tesla coil thing is geek overload for me. The other main comparison between the convention and Disney World involves a certain species of animal, other than human, that can be found at both places. And I'm talking about a real animal, not something like a Wookie (although I did see one of those too). I've got to edit down those pictures first though.
[This attachment has been purged. Older attachments are purged from time to time to conserve disk space. Please feel free to repost your image.]
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