Heads up! MYTHBUSTERS season premiere tonight at 9 Eastern!

[Christopher]

Up close, it was clearly real flame. I did see a bit of posterization in the long shot, but I took that to be just an artifact of the video's resolution, though it could've been a function of the compositing.

Either way, "CGI" is the wrong term for that. That stands for computer-generated imagery, i.e. an image created entirely within a computer with no live photographed elements. I've seen CGI fire and it looks totally fake. At most, this was a live pyro element that was digitally composited into the scene in the few long shots they did. That's not computer-generated, just computer-manipulated.

[Mr. Adventure]

You guys might find this interesting:
http://file-magazine.com/tv/dancing-pigeons-ritalin

[Christopher]

^Interesting... it says they shot it entirely in-camera. So either the fire and vapor were real and full-scale or there was some kind of forced-perspective illusion going on -- but in the latter case there would've needed to be some VFX for the interactive lighting on the ground beneath the flame.

It's possible this could be real; the main issue is that the cloud from the fire extinguisher seems improbably big. But then, it was shot at night and the cloud was brightly lit, so that might've made it seem bigger and more impressive than Adam's small-scale test in the daytime. And the fire stream here seems smaller than the one from Jamie's flamethrower. It's possible Jamie just overbuilt his.

Also, if it was real, then timing was an issue. It was edited to look like the flamethrower fired first, but in the long shots, compared to what the Mythbusters achieved, it looked to me like the extinguisher must've fired first and gotten up a good wall of CO2 to block the flame.

But there's still one reason to suspect VFX were used in the long shots, and that's safety. If this was a professionally produced music video instead of a bunch of idiots goofing around, then I doubt they would've permitted one person to fire a flamethrower directly toward another person with only a fire extinguisher as protection.

[Mr. Adventure]

Christopher wrote:

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If this was a professionally produced music video instead of a bunch of idiots goofing around, then I doubt they would've permitted one person to fire a flamethrower directly toward another person with only a fire extinguisher as protection.

It is a professional production, this was a commercial promotion for Diesel clothing and the band Dancing Pigeons.

http://vimeo.com/13639493 note the credits
http://www.blinkprods.com/#artist_tomasmankovsky

[Gep Malakai]

Just finished watching it; pretty good episode. I was more surprised by the dust cloud kidnapping than the title myth. Who knew a fire extinguisher can block IR cameras?

Christopher wrote:

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^Interesting... it says they shot it entirely in-camera. So either the fire and vapor were real and full-scale or there was some kind of forced-perspective illusion going on -- but in the latter case there would've needed to be some VFX for the interactive lighting on the ground beneath the flame.
...
But there's still one reason to suspect VFX were used in the long shots, and that's safety. If this was a professionally produced music video instead of a bunch of idiots goofing around, then I doubt they would've permitted one person to fire a flamethrower directly toward another person with only a fire extinguisher as protection.

I think you could get away with a forced perspective-type gag in one or two ways without needing to VFX anything. As you said, it looks like Jamie's flame thrower was overpowered, and the link Mr. Adventure provided said the ad people build a custom fire extinguisher to get the 30-foot plume of CO2. With that in mind, it appears the flame thrower and extinguisher used in the ad may have petered out of their own accord at the 30-foot mark without needing to meet head-on. So I'm thinking they either offset the actors by a few feet so they were firing past each other, or they were each angled a little bit so the two streams mixed at a spot off to one side. As these terrible photoshops show:

Option 1



Option 2



I spent way longer making those than I would care to admit.

The advantage of option 2 is that it would allow the interactive lighting at the tip of the extinguisher's blast, since the streams are actually mixing. On the other hand, if they knew in advance how far each would fire, they could have just spaced the actors far enough apart to be safe and had them fire at each other for real. Sounds like they controlled the props pretty carefully.

[Christopher]

^That's quite plausible, and I appreciate the effort you put into the graphics. Why didn't I think of that? And maybe in the long shots, the person with the extinguisher was wearing some kind of safety gear, just in case.

Still, the problem with the "petered out" idea is that, as I said, the stream from the flamethrower is travelling pretty straight across that entire 25-30 feet, not dipping much due to gravity. So it must've been shot out at considerable speed and could probably have reached the rest of the way, or nearly so. That could still be consistent with your model #2, though. We only saw a couple of shots of the flame and vapor interacting, so they could've simply cut away before the flamethrower stream moved much past the front of the vapor cloud.

[Forbin]

Meh. For some reason I was bored to tears this week. Except when Kari was on screen.

They sure do repeat the setup over and over and over and over and over and over and....

[Christopher]

Forbin wrote:

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They sure do repeat the setup over and over and over and over and over and over and....

I asked about that once over on the MB fan club forum, and apparently there's a reason the producers do that. IIRC, it has something to do with the fact that the show is often shown in classrooms and maybe they only have time to show one or two segments per class, so it helps to recap the basics of the myth at the top of each segment.

[Gep Malakai]

Interesting. I'd always figured it was to orient any viewers who drop in on the middle of the episode, since the recaps tend to come when they cut back to any given build after a commercial break. (Like how dramas will often have somebody restate whatever the dramatic hook was at the end of the previous act. Character 1: "The macguffan is gone!" Cut to commercial. Cut back to show. Character 2: "What do you mean, the macguffan is gone?" The drama picks up where they left off.)

[Redfern]

Forbin wrote:

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...I was bored to tears this week. Except when Kari was on screen.

Oh, so true! It's never boring when Kari's present!

Tell me; who else here was disappointed that Kari was not present (or in a condition) to wear the infamous Theiss miniskirt uniform when they analyzed the "Gorn cannon" myth?

Sincerely,

Bill

[Forbin]

Christopher wrote:

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I asked about that once over on the MB fan club forum, and apparently there's a reason the producers do that. IIRC, it has something to do with the fact that the show is often shown in classrooms and maybe they only have time to show one or two segments per class, so it helps to recap the basics of the myth at the top of each segment.

Well, that's a darn rational explanation, then.

Always makes me feel like I'm being treated like an idiot with no - SQUIRREL! - attention span, though.

[Christopher]

All automotive myths this week.

Square Wheels: I'm surprised they went right to full-scale with this instead of doing some small-scale tests. Instead they did the bench tests later, after the initial full-scale test failed. Or did they? Maybe they actually started small-scale, but edited it in a different order to create the desired narrative.

Anyway, the results were interesting. Although the ride did get relatively smoother in the cab as the wheels spun faster, the square wheels made things incredibly rough for the wheels and axles themselves, which is what really matters. The non-uniform shape meant there were constantly shifting forces pushing things off-balance and creating torques on the axles and connections and such, even aside from the constant impacts. And of course the tires came off easily because they had only four points of contact.

I was surprised that Jamie's idea about climbing in soft dirt didn't work. His reasoning certainly seemed sound. I'd like to see it tested, not for hill-climbing, but for avoiding getting stuck in the mud like he was talking about.

I'm a little disappointed that they measured vibration with electronic sensors. They've found more creative ways to do that in the past, like in that driving-on-a-bumpy-road myth where they used glasses filled with water or something. But I guess that would've been too fragile here.


Conjoined cars: Interesting that they know this kind of conjoining can actually happen, although I doubt it would be stable through those kinds of maneuvers if it weren't specially rigged. I liked the framework they came up with to join the cars' frames together; that was clever.

The steering issue was interesting, and obvious in hindsight; the wheels that turn are near the center of mass, so there's not a lot of leverage there. Still, I wondered if the corner turn would've worked better if both cars had turned their wheels in complementary directions. I mean, it sure worked in the spin test when they turned their wheels in opposing directions. So it's odd they didn't test that variation. Sure, maybe it wasn't in the movie, but they diverged from that when they reversed which car was exerting the force.


As for this week's Unchained Reaction ("Flight"), for once I actually agreed emphatically with the judges' decision. The artists' rig had some really beautiful elements, especially the finale with the ribbon dancer and the Chinese lanterns. It seemed to work better mechanically too, which I wouldn't have expected from a team of artists vis-a-vis a team of engineers.

Given that in previous episodes Adam and Jamie have looked askance on using team members themselves as triggers, it's surprising that they actually required the teams to incorporate live performers as "objects" in their rigs. Although Adam did have a point about both teams going for the simplest way of using the dancers -- though in their defense, it's hard to do more when they're sprung on you that late in the game.

[davejames]

The square wheel thing was definitely fun to watch. I certainly expected the ride would smooth out once they got going fast enough, but I wasn't sure the tires would actually hold up LONG enough for that (and they very nearly didn't).

Of couse the catch appeared to be that the faster you go, the less traction you have, because the tires are skipping along and only contacting the ground at those 4 points.

I do wish they had tried the slower approach on the hill though. The tires might have functioned more like a tractor tread than the way they did it, where the spinning tires just dug giant holes in the dirt.

[Christopher]

^Uh, they did try a slower approach on the hill as their second try, and it didn't get them quite as far as the faster approach.

I wonder if part of the reason the ride was so rough was because they didn't have inflated tires, just the rubber strips against the metal rim. If they could've designed some kind of square inner tube thing to go around the wheel rims, would that have given a smoother ride? Or would the constant shock of the points hitting the ground over and over just rupture the inner tubes?

[Trekker4747]

I'm actually sort of disappointed Jamie and Adam didn't expend more effort to make a "proper" "square tire." But it seemed all they did was cut the tread off a regular tire and affixed to a square rim. I'd like to see them re-do this only make an ACTUAL, air-filled, tire.