Flickering Effect in Project

Daniel Tan · June 10, 2007

Hi all,

I'm shooting a scene where a 16mm projector is running in the back ground and the projection is serving as a kicker light for a character. I'm shooting with DVX100B and I want to have the projection light flicker. I would think this is a shutter adjustment so I tested out with different shutter speeds from 1/12 to 1/1000. But there was no flickering in the light.

How can I make the flickering happen? Please help.

Thank you.

Daniel

David Auner aac · June 10, 2007

I'm shooting a scene where a 16mm projector is running in the back ground and the projection is serving as a kicker light for a character. I'm shooting with DVX100B and I want to have the projection light flicker. I would think this is a shutter adjustment so I tested out with different shutter speeds from 1/12 to 1/1000. But there was no flickering in the light.

Hi Daniel,

is the intensity of the projection bright enough to see clearly? Maybe switch off all other fixtures before you try again.

From my experience with TV/computer monitors and video I know that you can usually get these very clean by using a variable shutter on a PVU camera. But you could also increase the very effect using that shutter. But there you'd have a shutter speed of say 1/47.98856th of a second. If I couldn't get in to look good I usually changed the refresh rate on the monitors if possible.

Can you do anything to your projectors' speed? Can't really help you there as my knowledge of film world is rather limited. If that won't work either I guess you'll have to simulate the flickering by using some other fixture and moving something of front of that.

Regards, Dave

pascal Boyer · June 10, 2007

hi ,

you can also use a flicker box .

Chris Keth · June 10, 2007

Since you're using a projector, I assume sound isn't a huge issue. You can always throw a hard light through a box fan and it will flicker. If you want to adjust the speed of the fan more precisely than the fan controls let you, put it on a dimmer.

Michael Nash · June 10, 2007

Are you sure you want an actual "flicker," or do you want the random pulsing and color change that you would get from the projected images? You normally wouldn't see flicker in the projected beam of a movie image -- which is exactly why you're not seeing it on camera. You could experiment with running different types of movies through the projector, if you need to see the actual projector and beam on camera.

Rick Sharf · June 11, 2007

Does your projector have a speed knob? I just used an 8MM projector on my shoot and to get the desired effect we just slowed down the speed on the projector. It could be bad for the motor but you could put the projector on a dimmer, something like http://www.harborfreight.com/cpi/ctaf/disp...temnumber=43060

Just be mindful of the motor, and try not to burn it out of you choose this route.

these are amazing dimmers by the way, gotta love the 15 amp for $10.

Rajavel Olhiveeran · June 11, 2007

hi all

the flickering effect on FILM was beautifully created for the flashback seq in 'ILLUSIONIST'...wonder how...wish someone gives ideas on that....thanks

cheers

rajavel

rohtash chandel · June 13, 2007

i have doubts about flickering effect for a projection screen as it is more of a sudden change in colour and intensity of light

we recently did a shoot which required the same effect, we bounced two pars of the 6' by 4' both placed at two ends and had two guys operating colourd gels in front of the lights(blue, green cosmetic peach cosmetic and occasional white light), the change of colours and intesity on the face of the actors who were suppose to be sitting in front of projection screen was looking perfect . we were shooting against the projector it was mendatory to have the shaft created by the projector, so we placed a 2k with a snoot on it to get the effet it was looking just fine although there was a problem regarding the colour and intensity of light from the projector as it has to change in relation to the colour and the intensity of the light on actors face, which could be easily done later on smoke

Hal Smith · June 13, 2007

If you see "Nancy Drew" and like the projection effect in it, I can put you in touch with the person who rented the antique projector to Warner Brothers and ran it on the set. He'll have some knowledge of what was done. I'd give you his name, etc. but he and I hang out on a forum that requires more than just registration to join. (No, it's not a porn forum but it is a forum that chooses its members for a very good, practical reason).

edward read · June 13, 2007

On Chappelle's Show we used the leko through a box fan technique used above for the flicker effect. We pulled the guards off the fan (caution!) and ran it through a variac (autotransformer). The variac allowed us to vary the fan speed to monitor. The screen flash can be done with 2 flicker boxes controlling baby's shooting at a griff. frame. Gel one baby in 1/2 blue and the other in 1/4 CTO (season to taste of course). For the flicker effect I find a DF50 hazer is a great look.