# A Mushroom Cloud to "wow the audience"



## shannonlusk81 (Jun 14, 2017)

Lord save me, My artistic director has decided after a two year run that the video of an atomic bomb test isn't enough and he'd like to replicate a mushroom cloud on stage.

We have a vertical fogger currently mounted under the center of the stage for an unrelated effect so I'm hopeful that someone, anyone, might have suggestions for a way to use this fogger to make said cloud.

All other suggestions are welcomed too, I'm just at a complete loss...


----------



## sk8rsdad (Jun 14, 2017)

The physics of mushroom clouds make it difficult to fake theatrically. You need a rapidly rising column of hot gas hitting a cold, dense layer of air where it disperses. Something like a Chauvet Geyser could work to emulate the rising column. You might be able to use some sort of obstruction or downdraft fan to get it to form the mushroom cap.

At around the 1:10 mark of this video there's a geyser pointing downward at the floor that looks about right, except it's upside down.


----------



## Skervald (Jun 15, 2017)

Wow. Fun project. Here are a few random thoughts:

As @sk8rsdad said, it would be interesting to experiment with some sort of downdraft above your current fogger. Fan speed would be critical as you'd have to be careful not to disperse the verticle column.
There are a lot of factors to consider (timing, lighting, set configuration, desired height/ size of cloud, the output of fogger, etc.) but would it be possible to put some kind of physical barrier over the vertical fogger that wouldn't be visible? @sk8rsdad is right, the upside down geyser looks about right because it spreads out when the fog hits the floor. If you could replicate this right side up, you might have something.
I think a quicker dispersing fluid would help define the shape a bit.
Could you use multiple foggers somehow? I'm sure there are others but those geysers can be mounted sideways as well as upside down. Perhaps your current fogger functions as the verticle column and a couple more get flown in to form the mushroom top. Again, production details, the space, and budget are going to dictate how possible this is.
Please post your experiments and final product here. I'd love to see what you come up with.


----------



## EdSavoie (Jun 15, 2017)

The only problem i can think of with foggers on top facing down is that theit would visibly be shooting downwards as opposed to looking like a mushroom.

Perhaps first hitting the audience with some kind of blinder (as in a nuclear explosion) first would let you get aways with a bit more 

Perhaps sprinkling some fake snow in the house would also complement it nicely.


----------



## Amiers (Jun 15, 2017)

Off the top of my head I would say build your mushroom cloud out of some sheer fabric that can hold the fog in it enough to keep its form yet let it out to create the look for a mushroom cloud. Mix that with lighting and I think it could work pretty well.

I also would love to see what experiments you come up with as well.


Other idea. would be dry ice bomb on top and gysers on the bottom a well timed together shot of both of them could give you the desired effect.


----------



## Jay Ashworth (Jun 15, 2017)

I concur with "physics". This will be hard for the same reasons that water effects don't scale down well for miniature moviemaking.


----------



## shannonlusk81 (Jun 16, 2017)

Hi Guys, Thank you so much for all the input and suggestions!

A few more details: This is being used during the "opening credits" for a Zombie Burlesque show (it's okay to be a little jealous, it's pretty awesome). Our Zombies are "made" as a reaction to Nuclear Fallout, since the show is performed here in Vegas, we have a long history with Nuclear Test sites. So at the start of the show we have a fake news reel on a projector screen showing employees working at the Nuclear Test site, being productive for the war, wholesome 50's America all the way. At the end of the news reel there is a large Nuclear explosion with Mushroom cloud on screen. The following scene is the show "credits" where our zombie actors interact with a video wall behind them, essentially blending the live stage action with the screen at their back.

My artistic director would like a transition from this "projector screen in front" to "actors with a screen behind them" and wants the projector screen to be withdrawn as the mushroom cloud forms on screen to reveal a "real" mushroom cloud on stage.

We don't really have the space for Dry Ice during this transition (also that gets cost prohibitive when being run 6 nights a week for the foreseeable future). But I do think the rolling that dry ice naturally does would be perfect, it's a bummer it won't work for us in this instance. We also can't use any kind of structure that can't be VERY quickly struck from the stage.

I'm leaning towards using some sort of flat horizontal surface to manipulate the top of the fog plume into a mushroom cap. We might even be able to use a performer holding some sort of signage that would then be pulled up to reveal the words "Credits" sort of like a ring girl at a boxing match? Hokey or brilliant?


----------



## venuetech (Jun 16, 2017)

I'm thinking of that air puff gun that was a rage 10 or so years ago, airzooka . Make a larger vertical version of that device, fill it with a cold fog. Then shoot it off.
cold fog is the key, finding the right thrust will be the challenge
I find this is called a vortex ring gun and a common big version is made from a plastic trash can.


----------



## JD (Jun 16, 2017)

Keep it simple. Combine your fogger with a rear (or front) projection of a real blast.


----------



## Van (Jun 16, 2017)

I was thinking the same thing as @venuetech. The air zooka or a facsimile can produce a smoke ring, like the smoke ring guns here: 
Me? I'd take a #5 wash tubm cut the bottom, replace the bottom with a rubber membrane, attach a pulling device, rigged to a motor or solenoid, Put a rigid cover with a big hole in it on top of the tub then duct a fog machine into the tub. Trigger the solenoid to release and you should get a be ol smoke ring. viewed front-on it's going to look like a mushroom cloud.... Or something like that.


----------



## shannonlusk81 (Jun 16, 2017)

venuetech said:


> I'm thinking of that air puff gun that was a rage 10 or so years ago, airzooka . Make a larger vertical version of that device, fill it with a cold fog. Then shoot it off.
> cold fog is the key, finding the right thrust will be the challenge
> I find this is called a vortex ring gun and a common big version is made from a plastic trash can.



The problem here is: How would we conceal this and/or strike it quickly?


----------



## Van (Jun 16, 2017)

shannonlusk81 said:


> The problem here is: How would we conceal this and/or strike it quickly?


The whole thing could be built into a roll-able box or you hid it behind a ground row... Or you tell the artistic director to go into Film...


----------



## venuetech (Jun 16, 2017)

shannonlusk81 said:


> The problem here is: How would we conceal this and/or strike it quickly?


I was thinking that it would get vaporized by the blast. Or go with the flow and disguise it like a fat boy bomb.
But it should be lightweight. Perhaps make like a collapsible cup. Make a trash can demonstration unit and see what can be done with that. Personally I think your director will want something that looks larger.


----------



## Amiers (Jun 17, 2017)

If this thing has to be struck fast I would drop something fabric wise from the ceiling that is shaped like a mushroom cloud , mix in lighting and shoot fog up it. 

And then as the effect is dissipating drop the fabric and strike. 

This is going to give you the biggest effect cause I also feel like he is gonna want it nuclear :0


----------



## shannonlusk81 (Jun 17, 2017)

Amiers said:


> If this thing has to be struck fast I would drop something fabric wise from the ceiling that is shaped like a mushroom cloud , mix in lighting and shoot fog up it.
> 
> And then as the effect is dissipating drop the fabric and strike.
> 
> This is going to give you the biggest effect cause I also feel like he is gonna want it nuclear :0



He is absolutely wanting something massive. 

I've checked the ceiling above our fogger and there's not much room for anything (We have 16 feet to the light rails and then a foot above them we have a solid grid, and the lights are densly packed on those rails so having a fabric or soft mesh piece flown in would be hard to conceal. BUT, we had a performer at one point who would be flown onstage from a platform on the side and we may be able to use that rig to fly out our Atomic Mushroom Cloud Guide, which could be kabukied offstage in a hurry via a rope.


----------



## Amiers (Jun 17, 2017)

If you can fit the effect in a 5gallon bucket then it won't take up any room and just tip the bucket effect drops and then follow the rest with a disconnect and quick strike.


----------



## SHCP (Jun 19, 2017)

Have you ruled out Pyro? A flashpot seems like it would work. You need a licensed Pyro person to do the effect.


----------



## gafftapegreenia (Jun 19, 2017)

What about a different approach. A blinder light cue, a loud explosion sound cue, and some floor drying fans or other wind machine. It would "feel" like an explosion, as opposed to just looking like one.


----------



## JD (Jun 19, 2017)

shannonlusk81 said:


> He is absolutely wanting something massive.


Be careful what you wish for!
Check out what smoke detectors are in use in the room, as well as any HVAC duct detectors. You wouldn't want those tripping on show night.


----------



## Logos (Jun 19, 2017)

Van said:


> I was thinking the same thing as @venuetech. The air zooka or a facsimile can produce a smoke ring, like the smoke ring guns here:
> Me? I'd take a #5 wash tubm cut the bottom, replace the bottom with a rubber membrane, attach a pulling device, rigged to a motor or solenoid, Put a rigid cover with a big hole in it on top of the tub then duct a fog machine into the tub. Trigger the solenoid to release and you should get a be ol smoke ring. viewed front-on it's going to look like a mushroom cloud.... Or something like that.



My lovely ex fiancee created exactly this for a shadow puppet 3D show back about 5 years. The difference was that it was for three weeks and she used a cardbard box rather than a plastic bin and operated the membrane by hand. Worked like a dream in a shadow puppet show. (Much smaller scale of course)


----------



## RonHebbard (Jun 19, 2017)

Logos said:


> My lovely ex fiancee created exactly this for a shadow puppet 3D show back about 5 years. The difference was that it was for three weeks and she used a cardbard box rather than a plastic bin and operated the membrane by hand. Worked like a dream in a shadow puppet show. (Much smaller scale of course)


I always giggle when you refer to your wife as your "lovely ex fiance". The first time I read it, some months ago, I admit it gave me pause but now that I've become more used to reading you I readily comprehend but still giggle none the less.
Good morning Tony. @Logos
Good night from Ron Hebbard.
Toodleoo!


----------



## Logos (Jun 20, 2017)

RonHebbard said:


> I always giggle when you refer to your wife as your "lovely ex fiance". The first time I read it, some months ago, I admit it gave me pause but now that I've become more used to reading you I readily comprehend but still giggle none the less.
> Good morning Tony. @Logos
> Good night from Ron Hebbard.
> Toodleoo!


Yeah, its fun. I got the idea indirectly from an elderly man who was a good friend who introduced his wife (his only wife of 50 years) as "This is my first wife Pauline."


----------



## RonHebbard (Jun 20, 2017)

Logos said:


> Yeah, its fun. I got the idea indirectly from an elderly man who was a good friend who introduced his wife (his only wife of 50 years) as "This is my first wife Pauline."


Sort of reminiscent of amateur radio / ham speak / Morse code abbreviations where YL's are young ladies and XYL's are, shall we say, more mature ladies. 
Toodleoo!
Ron Hebbard.


----------



## ruinexplorer (Jun 22, 2017)

shannonlusk81 said:


> a Zombie Burlesque show


Man, I've had the coupon that I picked up at the Zombie Apocalypse store for months and have never seen the show. Maybe I should take some time to do so. Maybe when @gafftaper and his lovely ex-fiancé are in town. :^)


----------



## gafftaper (Jun 22, 2017)

I've seen Boiling water poured into Liquid nitrogen a couple of times and it's not a perfect mushroom cloud, but it's not a bad fake. Put the liquid nitrogen in a tall container and you get a huge, instant explosion straight up. They just had it on America's Got Talent a couple weeks ago. Skip to the 5:00 point. 



ruinexplorer said:


> Maybe when @gafftaper and his lovely ex-fiancé are in town. :^)


 Yeah when we hit town tomorrow my lovely ex-fiancé is going to be looking for Cirque, not Zombies. Although given the current temperature we may end up zombies by Saturday. 

On the other hand if the coupon is good until November I'm sure we could put together a party of the guys here to go.


----------



## Amiers (Jun 22, 2017)

That looks like a winner. You can throw a trash can on wheels drop a ballon from the grid and let it rip.


----------



## bobgaggle (Jun 22, 2017)

I'm a little late to the party, but artistically, a 12' mushroom cloud is going to look kinda dumb next to a 6' dancer unless your scenery is forced perspective and its supposed to look like the bomb went off a mile away. Could you talk the director into doing a huge explosion? meaning, you see the column of gas rising up (like that nitrogen video) and the initial blast cloud at the ground (ideally with dry ice, but you could use a fog chiller), but the actual mushroom cap, in scale, would be way higher than the building so we can't see it? Saves you a lot of headache trying to make a mushroom of fog, and the effect would be bigger/more grandiose...

picture any space movie when they're doing a re entry, the zoomed out shot isn't that intense, but then they always cut to a close up of the heat shield glowing and flaming. That shot is always more intense, so with this idea, you're bringing the audience a lot closer to ground zero, so close you're immersed in the explosion, rather than watching it from a distance.


----------



## cadcoke5 (Jul 27, 2017)

I recall accidentally making a mushroom cloud on a small scale. Like an earlier poster, it was for a puppet show. Not having a fog machine, I improvised by putting a little talcum powder in a small bottle, and then feeding a short length of 1/2" dia tubing in and out of the bottle. By blowing on it, I could make a small cloud of "smoke". It actually was hard to not make a mushroom cloud.

The air-cannon type of device is not ideal for forming a mushroom cloud, because it tends to shoot out a fairly fast moving ring the size of the hole in the device. You would want something very slow moving and probably wider. So, aside from the space on the floor you would need, I don't think that is a good direction to go. I suspect that a cloth drop, perhaps with battens to hold out the shape, or a netted drop is the way to go. Just pile it onto the stage floor, and lift as the cloud would lift up. Add some projected light effect to the cloth to provide the general effect of a swirling cloud. If it is a netted drop, then you can back light. If the light source is near the drop, then any stray light going beyond the sides of the drop may even add an effect like of radiation streaming out from the cloud. If you don't have an effects light that will turn the pattern, even a pair of simple linenbach projectors, cross-fading may be enough. Or a pair of ellipsoids with leaf gobos in them.

I also like the fan effect that gafftapegreenia mentioned. Though, you will probably need to start the fans before the actual explosion to get them up to speed soon enough.

-Joe


----------

