View Full Version : Special Effects-Sparks
Bill Hamell May 4th, 2006, 05:42 PM I am looking to produce an electrical short, here is the scenario…
The talent brushes a group of wires and several wires “short out.”
Has anyone done this or know how to create the effect?
Thank you,
Bill
Marcus Marchesseault May 4th, 2006, 09:15 PM Um, turn off all the lights? Just kidding. A few quick flashes of bluish light and maybe a warm glow from the hot metal of the wire for a second or two is what a short looks like. I'm not stupid enough to have ever caused a short, but I've heard these things from friends and people like that. Yeah, that's it.
If you know anyone with a MIG welder, that will give a nearly perfect effect if the welding gas is turned off. With the gas off, the steel immediately oxidizes and pops and sizzles after the blue flash of the electric arc. Needless to say, if you do this with real special effects, electric arcs add an element of danger. You could instead use something like a small camera flash with some CTB gel added then rotoscope a bit of a glowing spark at the point of contact. Have the flash eminate from as close to the wires as possible and it should work. Fortunately, these things are easy to test.
Bill Hamell May 5th, 2006, 08:31 AM Marcus,
A MIG welder is one of the ideas I came up with as I have one.
I would however like the effect to be in place and be repeatable.
One thought I had was to use a condenser, charge it up use the effect then there would not be any lingering voltage to deal with..
I should add that I am not looking for a dead short but an intermittent one.
A second idea was to use an electric match without the pyrotechnics just the shunt between the wires. I was thinking that might give me a pop and some sparks.
Anyone out there making their own electric matches?
The scene is this, there had been an auto accident (there is smoke and fire under the hood (I have this looking good)) the talent goes back to the vehicle to retrieve his golf clubs and is scared back out of the vehicle when sparks fly from under the dashboard.
Thank you for replying. :-)
Bill
Marcus Marchesseault May 5th, 2006, 08:47 AM Sparks from a car's electrical system aren't dangerous unless they start a fire. Anyone who knows how to jump-start a car probably has this information. I know most movies pitch to morons, but you may also have some smart people watching. Also, anyone that goes into a burning car for golf clubs will look insane and probably wouldn't be scared by sparks. Perhaps the trunk could have some fire also? Besides, what would cause sparks in the trunk?
I hope you are faking the fire under the hood or perhaps this car has had all the flammable stuff like fuel and rubber removed?
Has anyone here witnessed a real car fire? The fire has intensity unlike anything else you have probably experienced. I drove past a burning car a few lanes over and the heat coming from it (through tinted windows) at that distance (~40 feet) was more intense than the heat from the sun on a cloudless day in summer. No sane person could get within 20 feet of a burning car without fire protective gear and some water. When cars go up in smoke, they really go hard and fast.
Bill Hamell May 5th, 2006, 09:37 AM Well let’s see… I pulled a drunk out of a burning car once and for my efforts he took a swing at me because I left his glasses in the consol. So yep I have seen a burning car.
I also was a SCCA Marshall and am quite familiar with gasoline and flame.
The engine fire is done with lights and smoke (fog.)
It is meant to be more of a smoldering fire than a fully involved vehicle fire and goes out fairly quickly.
I did the test with my car so you can be sure I was very careful, for the shoot I want the engine and fuel tank removed just for safety and ecological reasons. (No oil/fuel no cleanup.)
The driving shots will be done on a trailer. We will be using a wreck I just will not show the front end till after the crash. :-)
I don’t write it, I just give them what they want. :-)
His clubs are in the back seat. He sees the sparks as he is leaning in.
In the FWIW column it is a comedy and was funny when I read it.
Thanks,
Bill
Adam Keen May 5th, 2006, 03:04 PM I recommend checking out http://www.detonationfilms.com/ They have free video clips you can composite in. This is much safer.
That's also not as fun. For some DIY pyros, use thin strips of aluminum and a 12 volt battery. Use that to ignite flint that you gently scrape off. Flint dust makes nice sparks. You could also try fine magnet wire with a shellac coating. Knock some of the coating off a bundle then short out the 12V.
-Adam Keen
Bill Hamell May 5th, 2006, 06:30 PM Adam,
Thanks, I had for gotten about that site.
Thank you for the suggestions as well.
Bill
K. Forman May 5th, 2006, 06:48 PM Instead of using electrical sparks, try this instead. Using a black back ground, take a grinder to some steel, and shoot that. You can then lay it over your footage, shrink, position, and key out the black.
A little safer than mucking with electricity, especially if you're like me and Tim Taylor.
Marcus Marchesseault May 6th, 2006, 02:08 AM Thanks for the safety reassurance, Bill. Also, regarding realism - "In the FWIW column it is a comedy and was funny when I read it." Enough said. All is fair in a comedy. I've been seeing ridiculous things in "24" and the logic flaws really make it low-brow but I don't think they intend it to come across that way.
I really like the use of a pre-wrecked car. If the audience only knew...
I like Keith's idea, but use sparks from the MIG welder against a black background instead since they are genuine electric sparks. On the set, you could use a flash or strobe to tie the keyed-in effect into the scene. Don't forget to record some sound in case it sounds like a nice spark.
Bill Hamell May 6th, 2006, 06:58 AM I am getting some good ideas.
I will shoot a test with the grinder; I passed on that idea thinking it would not be realistic. However having Keith bring it up again had got me thinking about it again with a fresh perspective.
I will fire up the welder as well and see what we get; it looks like on detonationfilms.com they may have used a welder or plasma cutter for some of their effects. Thinking about it if I take a piece of steel and paint it black and drill a hole through the center of it, I could strike an arc on the wall of the hole from the back side.
Then the sparks would shoot out like I want.
Just one more note about safety, I am a mother hen about my talent and crew no one on a stage or set has ever been hurt when I have been in control of it and they never will.
As for electrical stuff my father owned an electrical business, I could ruff wire a building when I was eight years old, I could finish wire it by Jr. High. We do this for fun and it is no fun when people get hurt. Enough said. :-)
Thanks,
Bill
Thought I would add...
Day time test my car shot in the front yard.
http://cinebydesign.net/film/day-smoke-1.jpg
Night time test with "fire" ((frame grab) please for give the lenes shade on the right)
http://cinebydesign.net/film/night-smoke-1.jpg
Night shot of test set
http://cinebydesign.net/film/set-test.jpg
Marcus Marchesseault May 6th, 2006, 09:35 AM I looked at your photos and came up with a bunch of ideas.
A trunk/dome light could come on when the trunk is opened. It would illuminate the actor a bit. Suddenly, when the spark occurs, it would flicker out. That could add to the effect of the scene. The actor would still need to be lit by the key light and maybe a hair light/kicker. You could probably tap into the dome light itself or fake one with a studio light in the car. A switch could be sent out to a gaffer.
Regarding the key light. I really like the first shot in the daytime (evening) where the sun is streaming through the steam/smoke. I also think your key light reveals itself too much since the rear corner panel is noticeably brighter than the front of the car. There is also a big highlight on the rear wheel that gives away the light's position. Simulated moonlight seems to work better if it is side or back lit. Perhaps you could move it to camera left instead of camera right. That way there could be some streaming shadows cast from the tree through the smoke. I also think the light needs to be moved further away so the inverse-square effect is lessened. The part of the scene closer to the light is significantly brighter than the rest. It seems that your light is bright enough to deal with greater distance.
I like the look of the "fire" and would like to see some cast in the wheel well and under the car to accent those details and make it a bit more dramatic. The bent hood revealing the light is perfect, but I would like to see a bit more.
Regarding safety, I think the sandbag slipped off the leg of your key light. ;)
Bill Hamell May 7th, 2006, 12:52 PM I like the dome light idea I had not thought of that.
I agree completely with your assessment of the key light.
I did see that highlight on the rear wheel; however my goal that night was the engine fire. I did not really care about it just made a mental note of it.
Moving the key to camera left and back… we agree again.
I had debated whether to use a 1k or a 2k for he test I went with the 2k so I could pull the 2k back or just use a 1k instead.
Here are my thoughts…
Take what is the key now and make it a back quarter light camera left placed high and hitting just before the backside of the vehicle. Then light the talent with a combination of a side light (fill) camera right and a quarter light (key) camera left, letting the backlight act as a "rim" light as well. The talents lights will have to be flagged to keep any light from striking the vehicle or the ground. They will be the “unknown light source.” :-)
The wheel well light is also a good idea I will work on that. I only had three working lamps for the fire (more parts due here Tuesday UPS.) One for under the vehicle is a must.
Sorry not going to bend up my hood for the test!!! :-)
Good idea though.
Regarding safety, good eyes I had removed that bag to start the tear down when, I remembered I had not takes stills of the set-up. I was the only one on the test set and if there was even one more person on set I would have replaced it.
Bill
Marcus Marchesseault May 7th, 2006, 07:20 PM I was just giving you a hard time about the sandbag. :)
I didn't mean to imply that you should bend the hood further. It looks fine as it is. People know there is not usually a gap between hood and fender and a fiery glow coming from that gap is a perfect indication that all is not well. The "more" I mentioned is more "fire" light coming from under the car.
I agree with the 2k placed further from the car to reduce the brightness ramp-up that occurs with close light sources. The inverse-square law is often my biggest problem with lighting since I need to put my low-budget weaker lights close to the talent. It is always a struggle to prevent giving away the light source when a big highlight suddenly appears when someone walks too close.
Peter Jefferson May 8th, 2006, 07:07 AM i did this with a preshoot for a couples wedding video (of all things)
the thing to remember is that sound wil play a major part in this..
I used day for night effect chains (as the lights went out, so did the luminance of teh shot)
I also used Particle illusion to create the spark bursts (had a load of FLurou lights short circuit and blow their tubes..
PI is great for this, and blending it with PI, worked a treat. PI illuminated the "darkened" areas and made it look quite authentic
As ffor grinding through a metal plate.. u dotn have to do this.. u can do all these kind of effects in programs like fusion, PI, Combustion etc etc... and yes, they are photorealistic...
Bill Hamell May 10th, 2006, 02:57 PM Marcus
<I was just giving you a hard time about the sandbag. :)
That is how I took it. Still good eyes.
I was spinning humor on the hood thing.:-)
I agree more fire more flames, bigger, hotter burn that puppy down!! :-)
Seriously it needs to be brighter and needs to go into the wheel well and on the ground. My starter sockets arrived yesterday I will build the flicker box(s) this weekend. This will allow more lights to be used.
I spoke with Mario from Eliminator Lighting he suggested I use a Hazer instead of a Fogger for the longer scene times. It seems that all foggers have to reheat within 30 seconds to a minute and a half depending on the heater size. However hazers do not use a heater and can run for longer times so I will start looking for one. Eliminator does not make one. Their fog machines work well though.
I was lucky to get the Studio 2k a bargain at $175 I was thinking of backlighting the smoke through a 4x4 of Rosco 3011 tough silk orientated vertically I’m hoping to it will create a ray effect.
Then use a 650 and a 300 for the talent.
If the weather is good (it is supposed to rain this weekend) I will shoot a second test the following weekend.
Peter,
I download the Particle illusion demos which did you use Particle Illusion or Particle Illusion SE?
I could easily do the SE version at $99 and probably afford version 3 at $399, Combustion at $950 is out of the question.
Thank you for the suggestion.
Do you have the project .ipf files available and if so would you be willing to let me view your work? I would not use them just learn from them.
One thing I was disappointed in was you can not skew the particles on the Z access.
I would like to place the particles canted from back to front. Maybe I just have not worked long enough to figure out how to do this.
Thank you to both of you for the help.
Bill
Robert Martens May 10th, 2006, 05:15 PM The only way to approximate a depth effect in PI would be to animate the "zoom" property of your particles, and that's hard to get right; doing it in a compositing app would be the best way. That's the primary advantage of combustion when it comes to particles (plus the motion tracker it's got), though the PI engine is 2.0, I believe, while 3.0 is the most up to date.
Don't forget to check out the emitter libraries that have been released over the past few years (http://www.wondertouch.com/downloads.asp#IEL), there may be some good sparks in there. I started going through them as soon as I saw your post, if I find anything I'll let you know. With some tweaking--or total reworking, if need be--you might end up with something you like.
Update: Threw together a little emitter for you to look at, if you're interested: http://www.gyroshot.com/files/Spark Test.zip If the demo doesn't allow you to load libraries (I'm using a full copy of 3.0), you should be able to look at it with ShowIEL (http://www.wondertouch.com/showiel.asp).
That's only a taste, of course, and one could add to it as necessary. Smoke, for example, or for a more complicated effect you could make use of so-called "super" emitters, to have the sparks break up at the end of their lives, forming extra trails (a Google image search for "sparks" reveals plenty of reference for that kind of thing).
Bill Hamell May 11th, 2006, 04:25 PM Robert,
Thanks for the help, I could not open the file the demos are looking for .IP3 or .IPF files. Thank for trying. I bookmarked the forum and will read through it.
I had Googled for spark effect but not just sparks da!
I will do that. It is a cool program I will probably get the full version next week.
Bill
Robert Martens May 12th, 2006, 12:36 AM The IP3 and IPF formats are particleillusion project files; what I sent you was an emitter library. You can load it by right-clicking in the area on the right side of the workspace in the program (where all the different emitters are listed) and selecting "Load library". It's only one particle type, but I thought it might help start you on the right path.
Bill Hamell May 12th, 2006, 01:37 AM Robert,
Thank you I can see it in the menu, however in the demo it is grayed out.
I can view it with the viewer.
Bill
Bill Hamell May 13th, 2006, 04:24 PM Here is my first attempt at fire and smoke I know this post started as sparks, however with the presets provided fire and smoke was easier to learn with.
I used the demo of PI V2 SE.
I imported a still image and added smoke and fire, I think it is a little intense, but hey it’s my fist time, I’ll learn. I am also just reading about how to do reflections so I have not added any yet.
Comments welcome.
http://cinebydesign.net/film/fire-smoke-1.avi 1.16mb
Bill
Marcus Marchesseault May 17th, 2006, 05:32 AM Although the quality of the graphic is good, I think just an occaisional tounge of flame popping out would look more realistic. A perfect curtain of fire seems too perfect to be real. I definitely think it has potential, but I would rather the smoke be generated on-set so it can interact with the lighting and shadow. I'm interested in seeing the test footage with the flicker box you made included.
Cole McDonald May 17th, 2006, 08:24 AM Since it's a static shot, if you wanted more realistic, you could build a replica of just that part of the hood in flat black and have practical smoke and fire (get a pro to do the burn). This can be composited over the main footage using a multiply to make the stuff look like it's coming out of the hood.
Bill Hamell May 17th, 2006, 05:39 PM Marcus,
I like your suggestions and have reduced the flames and made the smoke match the background better. Not quite there yet but better.
I agree about the smoke on set I have found out what I need and that is a Hazer, at $600 it will have to wait awhile. So I will do with the fog machine I now have. ($30)
Watch this video you will see the underlying color flashes this is the effect the box gives.
I had the starters hard wired in to the lamp cords. The box will make it easier though.
I wanted to shoot another test this weekend however the weather will veto that idea.
Cole,
I will have the engine pulled out of the wreck I will use, it is possible I could mix up some cold flame and use it for the effect then supplement in post as needed.
Too the lab Igor! ((blah ha ha)(evil laugh))
Anyhoo here’s the latest version…
http://cinebydesign.net/film/fire-smoke-2.avi 5 mb
It is a larger frame size so the effect shows better I also made it 15 secs long and it has a video background this time so the background smoke moves, as does the moth flying about my backlight. Interesting factoid every now and then you would see a puff of smoke from the broad light as a moth flew into it now if I could get more moths to sacrifice themselves I would not need a smoke machine!!! :-)
One more thing I found out what I need for the sparks they are called Omni short circuitors I have not found where to buy them yet, though I do know I will need to pull a temporary permit to buy them.
Bill
Cole McDonald May 17th, 2006, 07:48 PM that looks alot better!
Bill Hamell May 18th, 2006, 02:30 AM Thank you, I’m learning.
Robert,
You said you had both Discreets Combustion and ParticleIllusion V3 If I get ParticleIllusion V3would there be any reason to get Combustion as well?
Thanks,
Bill
Robert Martens May 18th, 2006, 07:31 AM Nice work on the fire, looks pretty good (though I think there's a little too much orange in there, might look better if it were a slightly darker color).
I can't say there's much reason to get Combustion if all you want is the particle effects; it's a great program, and has many (many) other features you might find useful, but I can't bring myself to suggest you spend all that money for a few shots with some simulated smoke/fire/sparks. The real advantage it would have in a scenario like this is the motion tracker, as I mentioned, but if worse comes to worst, I might be able to help you out with that (you send the shot, I track it and send back the data for you to import into PI). It's possible to keyframe the particles' positions by hand as well, which may make sense for you if the camera move is simple.
Bill Hamell May 18th, 2006, 01:21 PM Robert,
Thank you, for the information and the offer.
I think camera movement will be small if any in this series of shots It will come more into play when the talent starts interacting more. (By then the fire “WILL” have died off (large grin.)
Bill
Matt Sawyers June 17th, 2006, 02:19 PM Instead of using electrical sparks, try this instead. Using a black back ground, take a grinder to some steel, and shoot that. You can then lay it over your footage, shrink, position, and key out the black.
A little safer than mucking with electricity, especially if you're like me and Tim Taylor.
I would do this. Might even take a sparkler and hold it above the frame then overlay it.
Zack Vohaska June 24th, 2006, 12:19 AM A great resource as well is DetonationFilms.com -- they offer free stock footage of explosions, sparks, smoke, blood -- you need it for compositing, they at least have something. In addition to their free footage, they have pay-per-download and CD's for purchase with additional stock footage.
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