fluorescent lamp and flickering

[Scottie Mei]

Hi, I am shooting a low budget short. there is a scene set in a morgue that I would like to use flurescent lamps to get the green spike, but not sure which one should i get as there are cool white, warm white..etc..Also, I would like to get the flickering from flurescent lamps, but not sure if I should change the shutter angle to 90 or 45 degree. any feedback would be appreciated. thanks

[James Brown]

> fluorescent lamps to get the green spike,

 

If you want MORE green why not chuck some extra 1/2 + Green or WFG.

 

> I would like to get the flickering from flurescent lamps,

 

You can get the flickering by having one of your electrics crew hold the male end of the plug half into the socket and when it doesn't quite make contact it will flicker.

 

Regards James.

[Thomas Burns]

Scottie,

 

A flickering effect on commercial flourescent fixtures can be achieved by using a variac dimmer. Start with the unit at line voltage and slowly begin dimming down until you find the "sweet spot" where it begins to flicker. Good luck!

 

Best,

 

Thomas Burns

Electrician/Novice DP

Los Angeles

[Juan Guajardo]

Warm White is about 3000k to 3500k and Cool Withe is 4100k to 4200k and meaby add some CC15G for a greenish look

 

for the shutter remember that over 1/60 you will have flickering so it must be on 144° or less.

[Michael Nash]

It depends on what you mean by "flicker" -- do mean flicker erratically, like a fixture with faulty ballast (visible to the eye)? Or pulse on film beacuse it's out-of synch with the frame rate?

 

I got a cool effect once by putting a Kino on a Magic Gadget, with very irregular flickering. It's touchy though, you have to find a "sweet spot" where the voltage is enough to get the ballast to kick, but not turn fully on or not strike at all. Not sure what that may be doing to the ballast, though... ;)

[Scottie Mei]

Hey Michael,

 

Thanks for sharing your gig with me. :) I would like to get a visible flickering as a fixture with faulty ballast . I will try the magic gadget and try loose the male end of the fixture. does your kino+magic gadget gig gives you the flickering effect I am looking for? or it just trun out to be flashy kinda flickering? thanks.

 

Thanks Thomas

[Michael Nash]

A "Magic Gadget" is a special effects flicker box that you can program. It can vary the voltage, flicker rate and pattern. It's used for creating firelight effects, TV effects, and so on.

 

http://www.magicgadgets.com/

 

I can't say for sure how your fluorsecent ballast would react. Some commercial ballasts might just crap out altogether, who knows. And of course using dimmers or flicker boxes means you have to have a fixture with an Edison plug on one end -- practical ceiling-mounted fluorescents are hardwired into the building.