Jump to content


Photo

BLACK CYC STROBES


  • Please log in to reply
4 replies to this topic

#1 Dave Plake

Dave Plake
  • Basic Members
  • PipPip
  • 88 posts
  • 2nd Assistant Camera
  • Oahu

Posted 29 November 2007 - 06:42 PM

what I am trying to do is film someone in 35mm against a black cyc. I want this person to fall completely off to black on the sides and behind him etc. So that he is lit somewhat dramatically in and sourrounded by back...he falls off into the black void. Any suggestions on lighting this? Ie. which lights...how to light it?

The other thing I want to do is emulate poeple snapping his picture with strobes...however real still camera stobes are so quick that you can't really get illumination for a long enough duration to see the subject. I want the image to be completely black...and then you see the person..bam! because of the blast of light that illuminates him...then it falls off to complete blackness again. I like the idea of doing this with tungsten lights because they seem to fall off slower due to the fixtures still being hot and fading to black however I know a product like "lightning strike" customarily uses HMI.

I want to shoot this at 64 fps 45 mm 180 degree shutter.

In summation for the strobes part....I need it to be all black...the viewer sees nothing, then a flash of light long enough in duration so that the viewer can tell who the subject is, but short enough so that it looks like a camera has snapped his photo.

Any suggestions as to which tools to use how... wattage I will need to be able to support...links to articles...anything would be great.

Thanksl
D
  • 0

#2 Hal Smith

Hal Smith
  • Sustaining Members
  • 2280 posts
  • Cinematographer
  • OKC area

Posted 29 November 2007 - 06:50 PM

In summation for the strobes part....I need it to be all black...the viewer sees nothing, then a flash of light long enough in duration so that the viewer can tell who the subject is, but short enough so that it looks like a camera has snapped his photo.D

If you've got the budget, use an intelligent light like a High End Studio Color, MAC 2000, etc. They can be programmed to do what you want with full control over turn on / turn off / repetition rate. You'll also need an intelligent light board like one of the Whole Hogs to control the light on a DMX buss. Many intelligent lights use MSR (same technology as HMI) lamps with magnetic ballasts so you must use HMI safe frame rates.
  • 0

#3 Michael Nash

Michael Nash
  • Sustaining Members
  • 3330 posts
  • Cinematographer
  • Pasadena, CA

Posted 29 November 2007 - 08:43 PM

Check out Dataflash units for multiple programmable heads. Large tungsten lights will probably take way too long to "decay" at 64fps, and don't come to full brightness that quickly either. The larger the bulb, the longer it takes the filament to turn on and off. You might be able to get a longer duration but fast on/off with Unilux strobes.

As for lighting, just keep all your lights (including the strobes) well-flagged off of the black background.

Why 6-4 fps? That seems like an irregular number. And I assume 45mm was a typo...
  • 0

#4 Hal Smith

Hal Smith
  • Sustaining Members
  • 2280 posts
  • Cinematographer
  • OKC area

Posted 30 November 2007 - 12:08 AM

Check out Dataflash units for multiple programmable heads. ............

Dataflashes are nice on stage but strobe flashes are too short. Depending on the camera's shutter angle you are apt to lose at least half the flashes. The "beat" between the strobe rate and the fps rate is why filmed strobes often look so random - they don't look like live strobes because the flash rate appears to stutter on film. By going to intelligent lighting you can stretch out the on duration enough to get the flashes on for at least one entire frame.

I suspect out in Hollywood some does have something like Dataflashes that have been modified to take a sync pulse and phasing information from the camera - but I bet they don't rent cheap! On a mirror reflex camera you wouldn't see the flash because the light would only be present when the shutter was open - wouldn't that drive the average operator and video village denizen nuts.
  • 0

#5 Joseph Zizzo

Joseph Zizzo
  • Sustaining Members
  • 78 posts
  • Cinematographer
  • new york

Posted 30 November 2007 - 09:59 PM

a small lightening strikes unit is my personal preference for this type of effect. with a lightening strikes, you know you have a long enough decay, and you can hold the control unit in you hand and flash it yourself while you're shooting (or have the director or gaffer do it). you can vary the duration of your flash in real time, which i find to be a bit more expressive (or something) than intelligent lighting. and you have plenty of power if you want to overexpose.

from what i have heard recently, dataflash is being phased out. i used something new a couple of weeks ago, i will find out what it was for you. it was a less expensive option, like the dataflash, but there seemed to be more control over the duration of the flash...

anyway, it should look cool in slow motion! have fun...
  • 0


FJS International, LLC

rebotnix Technologies

Willys Widgets

Aerial Filmworks

Ritter Battery

Paralinx LLC

Rig Wheels Passport

Media Blackout - Custom Cables and AKS

Broadcast Solutions Inc

Opal

Visual Products

The Slider

Glidecam

CineTape

Technodolly

Abel Cine

Metropolis Post

Tai Audio

Wooden Camera

Gamma Ray Digital Inc

CineLab

Paralinx LLC

Willys Widgets

Metropolis Post

Technodolly

FJS International, LLC

Abel Cine

Wooden Camera

Ritter Battery

Rig Wheels Passport

Glidecam

CineLab

The Slider

Opal

Aerial Filmworks

Broadcast Solutions Inc

Visual Products

Gamma Ray Digital Inc

Tai Audio

rebotnix Technologies

Media Blackout - Custom Cables and AKS

CineTape