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Dust Particles Glitter

20th May 2007

How to get dust glitter in the air?

I’m about to test this but was wondering if anyone have done similar stuff before and could possibly give a few hints.

Camera is looking up a lift shaft (a set) and Id like to make a dusty feel, i.e. dust in the air (not smoke). So looking for some glitter f/x when back lit.

Thinking about cleaning out behind the sofa at home, bag what I find of dust and use that. Another idea is to use fullers earth. Any other ideas?

Flemming Jetmar
London DP


>>Camera is looking up a lift shaft (a set) and I d like to make a dusty >>feel, i.e. dust in the air (not smoke). So looking for some glitter f/x >>when back lit.

Keeping in mind that airborne dust does carry a risk of an explosion if the dust itself has a high calorific value and a naked flame/arc is present.

Not the sort of dust I'd like to breath in, but fibreglass dust from the insulating wool does a great job of sparkling in the air. Having worked on sites where labourers were throwing bales of the stuff about, I thought the effect of a sunbeam shining through the glittering dust was a visually pleasing effect. My voice going hoarse with the amount of breathed fibreglass wasn't such a nice effect.

If you went with something like the fibreglass wool dust, then just make sure that the minimum number of people are present for the effect and that anyone working in the area gets a disposable coverall and dust mask.

Clive Mitchell
http://www.bigclive.com


Also you may want to avoid the Fuller's earth; as most people believe it is toxic, though I personally am not sure. Your crew may have a problem with it.

What about clay silt, probably pick-up-able at any art supply store?

Jared Hoy
Los Angeles, CA
Gaffer || Bestboy


I would suggest getting a hazer to put atomised oil particles in the air and then supplementing this with fuller's earth for the dust effect.

Or just shake off your dirtiest flads and soundblankets nearby.

Mitch Gross
NYC DP


Baby powder . . .Float like a butterfly, smells like a babies bottom, or just use cornstarch, baby powders ingredient (but not as shiny).

Part of the key is airflow.

In a shaft you need to make sure low pressure is upstairs not down or nothing floats as air flow is down. And that difference in pressure needs to be regulated so it's just right.

Disclaimer : My opinions, thoughts, and beliefs are my own and may not reflect yours. The use of the pronouns "you, "some", and "many" to name a few are generalizations and without a proper name attached to them are not references to anyone reading my posts.

Walter Graff
Director
BlueSky Media, Inc.
888.435.5428 ext 31
Cell 917.217.9766
www.bluesky-web.com


How about trying flour?

It's certainly light enough to remain airborne for a while. Downside is, the risk of explosion that Clive pointed out.

Stuart Brereton
DP, UK


Flemming:

Why not just use glitter. I have a nine year old girl and I've got glitter everywhere. It is a little "heavy" and won't "float", but you said you were looking up a shaft so if the glitter is introduced at the top of the shaft and allowed to float down, that might work.

You could also overcrank a bit to heighten the floating effect. Lots of different glitter colours are available as well (I'm currently wearing red and gold). You might have to introduce side-light or front-light to get the proper reflective angle. I would suggest eye protection and camera protection to those near the fallout. Best wishes.

Sincerely,

John Sheeren
Camera Operator
1st AC
Houston, Texas


>>I've got glitter everywhere.

Well that just about sums up glitter. You'll never be able to clean it all up afterwards, it just turns up forever. (Ask a theatre cleaner.)

>>I would suggest eye protection and camera protection to those near >>the fallout. Best wishes.

For fine glitter like the precision cut Rosco stuff you should also wear breathing protection.

The weight of glitter is high, it tends to fall as opposed to floating in the air.

Clive Mitchell
http://www.bigclive.com


Thanks guys, very helpful.

I especially like the baby powder one and might be a bit less itchy than the insulation wool, but I’ll try both.

>>Clive Mitchell: '...airborne dust does carry a risk of an explosion if the >>dust itself has a high calorific value and a naked flame/arc is present'.

I know powderised dust can quite quickly catch on fire, I've seen that many times but explode? I guess if one put a detonator in a 2lbs flour canister it can explode but if just floating around in the air where lies the danger of explosion?

Flemming Jetmar
London DP


Flemming Jetmar wrote:

>>I know powderised dust can quite quickly catch on fire, I've seen that >>many times but explode? I guess if one put a detonator in a 2lbs flour >>canister it can explode but if just floating around in the air where lies >>the danger of explosion?

Google: Grain dust explosion and you'll know what Clive is talking about.

Brian Heller
IA 600 DP


So, I guess flour is out of the picture then?!
I learned something today, great.

Wonder if baby powder can ignite?

Hi ho hi ho off to test we go.

Flemming Jetmar
UK DP


When airborne the surface area of the particles is exponentially increased.

Ignition only happens on a surface in contact with oxygen (at least for the purpose of this discussion), so now there is a vastly greater ignition which creates a "flash fire" or a fireball. Escaping gases have to go somewhere with all of that energy suddenly released, so if they run into some form of containment such as an enclosed room, the result is an explosion. This is why they're so nervous about sparks near a grain elevator.

For a common example of the effects of increased surface area, think about how quickly the humidity in a bathroom rises when taking a shower compared to when taking a bath.

Mitch Gross
NYC DP



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