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Simulated Explosions


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#1 Jimmy

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Posted 03 March 2008 - 09:23 PM

Hi,

I'm looking for advice/suggestions on making small and large simulated explosions for amateur filmmakers. We have arranged budgets, locations etc. and I am now looking to sort the fine details, one of which is simulated artillery strikes.

The criteria/brief I am working to is for a smaller scale charge which can be used within 3-4 metres of 'actors' lying down on the ground, and larger ones where no one will be anywhere near them. The main criteria is to produce a convincing explosion with plenty of dust and debris in the air. One other factor is that we cannot dig into the ground on location to place charges, everything has to be placed on the ground (some of the land we are using is archaeologically sensitive).

All our charges are professionally sourced pyrotechnics which are fired electronically - nothing is homemade.

We've had a search of the internet and watched various other amateur films to see if we can work out how they are doing things. From looking at thing ab initio, it would appear that very lightweight materials are used - we've thought fullers earth (inert) and vermiculite in the main. We had planned to place a mix of materials in a card box with a maroon at the centre. Our only thought is that this will create a ball effect on detonation, and we really need a cone shape (I'm guessing some sort of tube or cone is needed).

Any comments, advice or pointers would be very much appreciated!

Jim

#2 YT2095

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Posted 04 March 2008 - 09:45 AM

it depends how good at editing you are, there Is a way frequently employed a bit like misdirection, where you could set off a charge on site, and have the effect fill the screen, then cut to another location where it IS ok to make a crater and set off another device there.
during the "Explosion" cut from one site to the other and let the crater site film play out, leaving it`s large hole effect.

because the explosion is so chaotic no one will notice the change over that you`re at a different location.
another way that works only if you don`t do it TOO often is to have something fly at the screen and block it for a second, that also gives another good editing place.

for long shots you can use shading techniques with black and gray powder paints to make it Look like craters when in actual fact it`s really quite flat and just an illusion.
the paint will wash away harmlessly the next time it rains.

Edited by YT2095, 04 March 2008 - 09:49 AM.

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#3 nikk75

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Posted 20 March 2008 - 07:15 PM

it depends how good at editing you are, there Is a way frequently employed a bit like misdirection, where you could set off a charge on site, and have the effect fill the screen, then cut to another location where it IS ok to make a crater and set off another device there.
during the "Explosion" cut from one site to the other and let the crater site film play out, leaving it`s large hole effect.

because the explosion is so chaotic no one will notice the change over that you`re at a different location.
another way that works only if you don`t do it TOO often is to have something fly at the screen and block it for a second, that also gives another good editing place.

for long shots you can use shading techniques with black and gray powder paints to make it Look like craters when in actual fact it`s really quite flat and just an illusion.
the paint will wash away harmlessly the next time it rains.

You could always cheat the shot using a compressed air mortar system, i recently built one and it works great.
want Big BOOOOOOM

#4 Steelrat

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Posted 22 March 2008 - 11:03 AM

You could always cheat the shot using a compressed air mortar system, i recently built one and it works great.



have a look at this doco http://www.youtube.c...feature=related

shows you how to make miniature explosions that look real , and besides its a jolly good doco on Richard Hammond presents Bloody Omaha (The Graphics)

phil
Explosive Compositions and children dont mix.

#5 Arthur Brown

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Posted 22 March 2008 - 12:29 PM

The tension of the battle scene is best aided by fast cutting so lots of short clips tell all. A puff of sand filling the frame, then a person staggering to a fall, then some red running across some uniform, --three studio shots that actually say when edited on film soldier killed by mine or big guns.

You don't film people being killed in reality! But the finished film looks as if you did.
http://www.movember.com/uk/home/

Keep mannequins and watermelons away from fireworks..they always get hurt..

#6 nikk75

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Posted 22 March 2008 - 05:45 PM

have a look at this doco http://www.youtube.c...feature=related

shows you how to make miniature explosions that look real , and besides its a jolly good doco on Richard Hammond presents Bloody Omaha (The Graphics)

phil

man thats impressive, but then you need the know how with the software
want Big BOOOOOOM

#7 ImpactWayne

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Posted 08 May 2008 - 06:48 PM

Hi Mate,

I'd use napthene charges, and other artillery shell simulators available from theatrical pyrotechnics ltd. they're spot on.

When i make debris rain, it tends to be a large steel drum, with a maroon holder, with a carboard lifting disk and a couple of bags on compost to rain down on to the actors,
compressed air bins are also the other option in close prox to the actors, you could perhaps use our air cannons which are normally used for confetti! but we've deployed them to fire water and compost on a few smaller film jobs.

give me a ring if you want to have a chat. 07880 527 077


Hi,

I'm looking for advice/suggestions on making small and large simulated explosions for amateur filmmakers. We have arranged budgets, locations etc. and I am now looking to sort the fine details, one of which is simulated artillery strikes.

The criteria/brief I am working to is for a smaller scale charge which can be used within 3-4 metres of 'actors' lying down on the ground, and larger ones where no one will be anywhere near them. The main criteria is to produce a convincing explosion with plenty of dust and debris in the air. One other factor is that we cannot dig into the ground on location to place charges, everything has to be placed on the ground (some of the land we are using is archaeologically sensitive).

All our charges are professionally sourced pyrotechnics which are fired electronically - nothing is homemade.

We've had a search of the internet and watched various other amateur films to see if we can work out how they are doing things. From looking at thing ab initio, it would appear that very lightweight materials are used - we've thought fullers earth (inert) and vermiculite in the main. We had planned to place a mix of materials in a card box with a maroon at the centre. Our only thought is that this will create a ball effect on detonation, and we really need a cone shape (I'm guessing some sort of tube or cone is needed).

Any comments, advice or pointers would be very much appreciated!

Jim



#8 Asteroid

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Posted 11 May 2008 - 10:37 AM

Any of the people at www.uksgc.co.uk would be more than willing to help you make an air cannon for close proximity explosions. I'm sure that using this method, the shape of the debris cloud could be changed easily, and not having to dig in would be easy too, although I suspect that it might be easier to use conventional methods for the larger explosions.
An air cannon is re-useable, and could have interchangeable barrels for different shapes, materials etc.




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