On Feb 26, 9:57 pm, atb3185 <atb3...@[EMAIL PROTECTED]
> wrote:
> I have a Le Maitre Neutron Pro Hazer and desire a low-hanging cloud-
> like effect. I know that dry ice is commonly used for a low-hanging
> foggy look, but is there a way to do it with haze?
Hey there,
The secret to getting a low hanging fog is to make whatever you're
pumping out cooler than the air around it. The drag about this is that
foggers and hazers have to heat up the fluid in order to particulate
it. While I've never tried cooling haze, it's theoretically possible.
The only thing you're going to run into is that haze, which is
designed to hang in the air much longer than standard fog, is going to
eventually reach the same temperature as the air and mix. I imagine
that you'd get, at best, a sort of denser cloud low, and less above.
This also depends on how big your room is, and how efficient your
hazer is, which with the Neutron Pro's can vary quite a bit.
Generally, to get the effect you are looking for without dry ice, you
need a good size fogger (one that puts out a lot of fog) and a chiller
unit. The fog gets chilled and hangs low in the air, but dissipates
before it matches the regular air temperature and rises. With all the
new fog formulations (there are some made specifically for this
effect), it's quite easy to get this effect with fog, and I can't say
for sure, since I'm not working on broadway, but my impression is that
dry ice is used much less than in days past.
There are several "Fog Chillers" made, but we make them ourselves.
Since I can't put drawings on this, it will be a lengthy explanation,
but the idea is just an insulted box and a radiator of some sort to
hold some ice and cool down the fog or haze. There are a variety of
ways to accomplish that. I've used all sorts of combinations of ice,
pipe, water coolers, auto radiators, and fans. The fog or haze needs a
little air where it's created by the hazer or fogger, otherwise the
particles turn right back into a liquid mess, but if you give it that,
you can pretty much do anything you want to it to heat it or cool it.
If you make your own chiller, I seriously recommend making it ahead of
time and experimenting with it, alot. You'll find that small changes
can make it work much better, and probably by the third or fourth time
you're using it, you'll figure out a bunch of those changes. It's
always a drag to be learning that stuff during the last few days of
tech and not let the designers or the director see the fog the way
it's actually going to be, or be able to show tell your crew exactly
how much ice, when to turn it on, what setting to use on the fan, etc.
Also note that your effect will vary depending on the weather... if
it's a colder day and the theater doesn't have good temperature
regulation, then your fog isn't going to hang as low as it has on the
warmer days.
The best homemade fog chiller I've used:
Get yourself a good size cooler (one that will hold a couple cases of
beer, minimum, and a cheap one, since you're going to destroy it) and
cut out an intake and output hole - we usually make them 4" round
holes, since that's the size to fit a Rosco fogger, which is what is
common here in Austin. The idea is to put one of those holes high on
one side and the other low on the other side. It doesn't really matter
which is which. It is usually better to put those holes on the narrow
ends, so that the fog has to travel a longer distance inside. I also
like to put a small clip fan on the output, to give plenty of airflow,
and with a hazer, which doesn't have an especially strong fan, you're
going to need it. With a good size fogger, it's own pressure pu****ng
the fog through is usually enough. The last step of the chiller is to
make some sort of radiator and try to fill the entire span of the
cooler, length and width, positioned halfway up vertically, between
the two holes you've made. The ideal would be a real auto radiator, as
you want some sort of metal with lots of surface area for the fog to
touch. We usually have to make our own - lots of copper tubing bent
back and forth with very little space between the runs works alright,
and has the benefit of holding water, just like a true radiator, which
gives it a bit more efficiency in cooling. From there, it's just a
matter of adding some ice - preferably dry ice, but if you're
seriously low budget then regular ice can work okay, and pumping the
fog or haze through the cooler. When it comes out the other side it
is, hopefully, colder than the regular air temperature, and will hang
low down.
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