Why you shouldn't have a naked flame in a powder shoot. Graphic example of what could go wrong!

Ponderance said

I have always wondered what happened once the metal powder trays began to rust; surely the chlorate corroded the tray, and don't you then have an even more unpredictable mixture once the rust is blended in?

 

That's why photography was such fun!  ;)

mph said

Ponderance said

I have always wondered what happened once the metal powder trays began to rust; surely the chlorate corroded the tray, and don't you then have an even more unpredictable mixture once the rust is blended in?

 

That's why photography was such fun!  ;)

Truly a life-altering hobby!

Ponderance said

Lightingman said

Ponderance said

Lightingman said

Flash BULB-FOIL-not powder.

Yes, but Tuppence is right; early flash powder did sometimes use aluminium powder (or a cost-effective mix of mostly aluminium plus some magnesium, a blend which happens to burn brighter).

Magnesium doesn't have any particularly special quality; it's the metal and oxidising agent which is the important bit.

Magnesium is more reactive than aluminium, and importantly aluminium rapidly develops an oxidative layer which especially in a finely reduced form-powder would tend to inhibit reaction significantly.

I think that is why they blended in magnesium to make the cheaper mixture work, but at this point my limited inorganic chemistry knowledge would fail me. 

I have always wondered what happened once the metal powder trays began to rust; surely the chlorate corroded the tray, and don't you then have an even more unpredictable mixture once the rust is added in? 

(more liberated oxygen during the reaction is my limited understanding)

Edited by Ponderance

The process could be quite dangerous, the movie versions aren't quite accurate. And yes the rust would add to the fun. It's the basic mixture for the MOAB!

Ponderance said

Tuppence said

Lightingman said

Tuppence said

Lightingman said

Tuppence said

boundtopleaseme said

Tuppence said

MidgePhoto said

Evaair said

what type of powders are flammable

Anything organic, I'd think.

Not only organic. Try aluminium or magnesium powder!

Please don't try aluminium or magnesium powder.

Various powders - coffee creamers and the like -  have been used for years in pyrotechnics to create a relatively safe, simulated explosion. Please note the term 'relatively'. It is done by pyrotechnicians, on a small scale, in a controlled method and environment. The actual flame is a conflation of millions of minute powder particles each of which ignites and burns out in a microsecond. The combined effect is spectacular but without any real substance.

Metal powders on the other hand burn at much higher temperatures. They have substance and mass and will do serious damage to people and property.

Admittedly, aluminium powder is an ingredient of thermite, but let's not forget it was widely used in photographic flash photography.

I suspect any powder has both mass and substance, so that adds little to the debate.

Aluminium powder was not used in photographic flash photography, the powder was finely divided magnesium mixed, usually with potassium perchlorate, a strong oxidising agent to propagate the burning process.

https://en.wikipedia.org/wiki/Flash_powder 

In pyrotechnics, not photography.

...and was once used for flashes in photography.

It looks like the first cost-effective flash bulbs were in fact aluminium foil:

https://photography.tutsplus.com/articles/a-brief-history-of-photographic-flash--photo-4249 

(That is not a joke image)

I always assumed it was always magnesium! :O

I have a small collection of weird and wonderful flashbulbs that I might photograph to share on PP. As well as a flashgun that holds 3 of the above pictured flashbulbs.

Edited by lampblack

I'm a trained pyrotechnician and a member of the Association Of Stage Pyrotechnicians. Doing any form of pyro work in a theatre was always worrying when you are aware of the dangers of dust combustion, the possibility of props (such as flour) catching alight and even gaffer tape catching alight (which looks like burning hot, liquid tar)

The dust of many materials in everyday use such as coal, wood, cork, grain, starch, sugar, certain metals, some dyes and intermediates, and many plastics, can form explosive dust clouds. Explosions of such clouds have caused some of the worst industrial accidents. On February 7, 2008, a huge explosion and fire occurred at the Imperial Sugar refinery northwest of Savannah, USA, killing 14 and injuring 38 others.

Yeah this happened recently in a nightclub somewhere abroad. Hundreds of people burned horribly and a lot of deaths

Seriously - this thread is a very good warning, and it has totally put me off any ideas of doing a flour shoot in my studio.

The explosion and the burns could be horrific.

and as you guys mention, it only takes one spark to set it off

(cheap flash trigger ?)

Tabitha Boydell - Photographer said

Yeah this happened recently in a nightclub somewhere abroad. Hundreds of people burned horribly and a lot of deaths

https://www.theguardian.com/world/2015/jun/27/fire-injures-200-people-party-taiwan-water-park 

Awful.