Special Effects Loads
- Thread starter msg.drew
- Start date
It might be CG, but if anyone was feeling suicidal, they could load real flash powder into blanks. Flash powder is finely ground aluminium, I poured a bunch of it from a firework once when I was little, wasn't sure what the silver stuff was so I lit it,.... couldn't see for about 20 seconds afterwards.
Isn't it magnesium that burns bright white?
- Location
- Thunder Bay ON Canada
Flash powder is usually a powdered metal, and a perchlorate, usually KCLO4. Never confine it. Never confine it. Never confine it. It's too brisant. It's really insane to work with the stuff anyways, unless you have an extremely valid reason. I know of one guy who does wetplate large format photography who uses it safely though very seldom... but ..... It's not something to trifle with.
I don't know what is in movie blanks, but i know it's not flash powder. It's too brisant to ever be confined, in any quantity whatsoever, and it burns too fast to see a flash out the end of a muzzle anyway.
As for the "colour" of the flash, it really doesn't matter, as long as the brightness of the flash exceeds the Dmax of the film or digital sensor, it will register as pure white or as close to it as the base layer of the film allows. That wouldn't be hard to do with a decent camera that you can control manually, to set the ISO, the shutter/frame capture rate and the aperture of the lens.
Maybe it's all CGI now, who knows, but it wouldn't have to be, if you had a real camera, not a point and shoot all-automatic consumer grade.
If I were doing it with a film camera I'd use a fast ISO, like 800/1600, a wide aperture like f2.8 or f2, and run the frame rate real SLooooooooowwwwwW. You'd catch every flash and they'd look very bright. You'd have shallow depth of field and it would be a bit grainy though. Meh.. there's always a trade off with photography.
I don't know what is in movie blanks, but i know it's not flash powder. It's too brisant to ever be confined, in any quantity whatsoever, and it burns too fast to see a flash out the end of a muzzle anyway.
As for the "colour" of the flash, it really doesn't matter, as long as the brightness of the flash exceeds the Dmax of the film or digital sensor, it will register as pure white or as close to it as the base layer of the film allows. That wouldn't be hard to do with a decent camera that you can control manually, to set the ISO, the shutter/frame capture rate and the aperture of the lens.
Maybe it's all CGI now, who knows, but it wouldn't have to be, if you had a real camera, not a point and shoot all-automatic consumer grade.
If I were doing it with a film camera I'd use a fast ISO, like 800/1600, a wide aperture like f2.8 or f2, and run the frame rate real SLooooooooowwwwwW. You'd catch every flash and they'd look very bright. You'd have shallow depth of field and it would be a bit grainy though. Meh.. there's always a trade off with photography.
- Location
- Thunder Bay ON Canada
I see someone was checking out the girls instead of paying attention in high school physics!
Colour is a function of EM wavelength emissions, and wavelength is a fuction of temperature.
So... liquid iron, or solid tungsten or burning magnesium or glass or molten rock or anything at all that's at the right temperature; above about 6000 kelvin (approx 5700deg C) is going to emit white looking light to the human eye.
Film or digital sensors can react differently to very bright lights, they have what is called latitude, beyond which they don't accurately reflect what they "see". A blacksmith can and does use the colour of hot iron to estimate it's temperature.
Well theres that, but then theres also the auto ignition temperature of certain metals which won't allow you to burn them at higher temperatures. One way blacksmiths also gauge the temp is by looking for sparks flying off the steel when it comes out of the forge, at that point the metal is undergoing combustion leaving pits all over the surface and their piece is ruined.
Magnesium is reactive, but aluminium readily oxidizes, giving rize to all those stupid thermite experiments of aluminium reducing, iron oxide. Replace the iron oxide with an even stronger oxidizer like potassium nitrate in blackpowder and you've got an explosively fast reaction.
Magnesium is reactive, but aluminium readily oxidizes, giving rize to all those stupid thermite experiments of aluminium reducing, iron oxide. Replace the iron oxide with an even stronger oxidizer like potassium nitrate in blackpowder and you've got an explosively fast reaction.
