Creating shafts of light

[Craig Bradley]

Does anyone here have experience creating shafts of light, as seen in things like Citizen Kane, X-Files, Noirs, etc? Are the main components heavy directed lighting, high-contrast composition, diffusion in the air (smoke, humidity, etc.), or something else completely.

I'll be doing it in colour DV, but finishing in black-and-white. Any suggestions would be welcome.

Thanks in advance,
--Craig

[Ken Tanaka]

Done as a practical effect, dark-ish background, fresnel light (perhaps screened through a gobo), and some form of airborne diffusion such as a fog machine.

[Richard Alvarez]

elipsoidal would allow a very cohesive look to a shaft as well.

[Boyd Ostroff]

Like Ken says, the key is having an intense backlight against a dark background plus some sort of haze effect. You can rent smoke/haze machines at your local theatrical supplier. Be aware that the health issues from these machines is a really controversial topic these days when it comes to performers, crews and their unions however.

I would also agree with Richard that an ellipsoidal reflector spotlight (such as the ETC Source Four) with a gobo (also called "template") can give really interesting effects in haze. Here are a couple examples:

http://tech.operaphilly.com/sets/flute/pix2001/1/7.jpeg
http://tech.operaphilly.com/sets/flu...2001/2/14.jpeg

[Rob Lohman]

In theory you could also do it in "post" with a 3D volumetric
render engine (like lightwave has for example) or fake it with
a transparent 3D object with special textures. Ofcourse you can't
beat the real deal, especially if you want objects / people to
interact with it.

[Jeff Patnaude]

Do you have access to any large Mole lights or Arri lights 2k or bigger? A 5k Senior pounded through window blinds works well. As the others stated, you have to have "atmosphere" in the form of haze/fog.
Your ambient light levels will be important.

I have seen aerosol cans of haze. Anyone use them before?

Jeff Patnaude

[Jacques Mersereau]

I've used the canned smoke and found it works very well.

[Richard Veil]

You have to make your own call on the amount
but smoke gives you the best canvas to gets shafts
of light. I have no idea if they can hold up but Radio shack has a smoke machine.... anybody ever use it?????
I have only used rosco

r

[Jacques Mersereau]

My boss picked up a cheap smoke machine at Meijers
(a regional super store chain) for
$49. It works pretty good, but like most cheap machines its
output is not continuous. He went back to get a couple more
and they were sold out.

Incense does a good job too and smells better (if you choose wisely).

[Wayne Orr]

Remember, when working with "smoke" or "foggers," you have to be in a confined space, with no air conditioning, or your effect will dissipate before your eyes.

Wayne Orr, SOC

[Boyd Ostroff]

By the same token, you might want to educate yourself regarding the nature of any smoke/haze efffects used in a poorly ventillated confined space. This is a particularly hot topic these days in the entertainment industry with a number of union grievances and lawsuits arising from the use of such effects. You could be opening yourself up to some liability by exposing actors and/or crew to smoke during an extended shoot.

One recent study "Atmospheric Effects in the Entertainment Industry: Constituents, Exposures and Health Effects" may be found at this link

[Jacques Mersereau]

Since we were talking about the lowest of the low end, I didn't
mention the high end. The high end and best imo are
the MDG smoke and haze machines. The smoke they produce is the smallest
particulant there is and can pass right though a hepa filter.

The MDG guys told me they are the only ones approved for
Broadway because the smoke/haze doesn't smell and has
almost no effect on actors/singers throats. In the world of divas
that really matters.

NOT cheap . . . like $3500 for the top of the line, but a 10 year
guarantee and built to last.

We had one in the video studio and this is the only machine that
didn't set off the fire alarm . . . even when the haze got thick!

[Kirk Candlish]

Could you post a link for the MDG machines ?

I did a search online but didn't find them.

[Boyd Ostroff]

Their website is "under construction" however you can download their brochures and specs here

I've used their "Atmosphere" machines before and was very impressed. The haze consists of mineral oil in tiny quantities. One possible downside of these machines is that they require an outboard CO2 tank which may need changing depending on how long you run the machine (I think we got through 2 rehearsals and 2 performances on the same tank however).

The nice thing about oil-based haze is that it disperses very evenly and hangs in the air for a long time. Unfortunately our singers union in Philadelphia only accepts water based haze so we can't use these, although they have indicated a willingness to look at the specs and MSDS if we want to make a switch in the future.

If you're interested in fog/haze then the other companies worth looking at are CITC and LeMaitre and of course Rosco.

[Kirk Candlish]

Thank you Boyd, much appreciated.