Hey everybody, hope you all had a nice christmas. Anyways, I'm in pre production for a short war comedy, which i'll hopefully shoot or at least start shooting over this next week. Anyways, my script calls for about four explosions. For Christmas I got this book, in it it talks about making fireball type explosions, my using a muzzle loading fireless propellant called pyrodex, using a wire igniter, and putting fine flour over it, then when you touch the other end of the wire to a car battery the pyrodex goes off and ignites the flour. has anyone tried this? and does it work? safe? etc... Thanks

http://www.detonationfilms.com

safe, free, easy to use.

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and does it work? safe?

A match isn't safe if a dummy lights it. Stick with the stock footage at detonationfilms, you'll live longer.

umm, pyrodex is a brand of a smokeless gunpowder, not a fireless propellant. It can be very dangerous and highly illegal to use the way you want to without being licensed and permitted.

Have you looked at the flour/powdered creamer mortars? By using compressed air (even from something like a hudson sprayer), you atomize the flour/creamer and somehow ignite it. It's still pyro so very very dangerous (and possibly illegal). But at least it's not using explosives. Detonation films may have a tutorial on this too.

thanks guys. I'll try both of those ideas and decide which one works best. Oh, and Joren, is this basically what you're talking about?

Why don't you just add the explosions in during post-production? That way you don't blow your head off.

that what the stock footage from detonation films is for. As for doing it in post or not, there are pro's and con's for each option, for instance, if you don't do it in post, you run the risk of, as you said, blowing your head off, but if you don't do in production, your actors don't know when to react and don't really have anything to work with, which makes their job a lot harder.

... plus chances are doing it in post will yield a very different look than doing it physically. At the student level, most people don't have the skills to composite a stock explosion in a way where it interacts with the surroundings in a believable way. (ooo, that sort of sounds like a challenge!)

It does sort of, doesn't it? You're just pushing me closer and closer to upgrade from After Effects 3 so I can actually use it again...

After Effects 3? God damn.

Yeah. It's scary. It used to run alright in classic, under emulation, but not on my newer computer. I REALLY need to buy the new one.

i did a clip once where we jumped off a roof, then added an explosion afterwards, it turned out alright, except there wasn't any debris or anything. i'd put it up somewhere but idk where it went, lol.

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At the student level, most people don't have the skills to composite a stock explosion in a way where it interacts with the surroundings in a believable way. (ooo, that sort of sounds like a challenge!)

Heh, most people don't at the "Hollywood" level, either Doing anything with practical effects will nearly always yield better results than relying on CGI - especially for explosions.

detonation films isn't cgi, it's just stock explosions, but you gotta composite them in.

I know. I should have said "CGI or compositing excessively"... compositing has its place, but is best when used subtly.