Jump to content


Photo

flicker trouble


  • Please log in to reply
4 replies to this topic

#1 Thomas Smith

Thomas Smith
  • Basic Members
  • PipPip
  • 35 posts
  • Cinematographer
  • Paris

Posted 18 August 2008 - 03:31 PM

Hi,
What's the exact shutter angle to avoid flicker in a 50hz country at 23.98P?
I'm going to shoot with fluorescent lights and don't have electronic ballasts.

Thank you in advance.
  • 0

#2 John Brawley

John Brawley
  • Sustaining Members
  • 834 posts
  • Cinematographer
  • Atlanta Georgia

Posted 18 August 2008 - 04:41 PM

Hi,
What's the exact shutter angle to avoid flicker in a 50hz country at 23.98P?
I'm going to shoot with fluorescent lights and don't have electronic ballasts.

Thank you in advance.



You should be fine. We shoot at 24 FPS all the time with no worries. If you really wanted to be fussy you could shoot at 172.8.

jb
  • 0

#3 Nathan Martin

Nathan Martin
  • Basic Members
  • PipPip
  • 61 posts
  • Cinematographer
  • Sydney Australia

Posted 18 August 2008 - 08:39 PM

as long as the fluorescents arent really old they should have a high cri, so they should be fine.
  • 0

#4 Thomas Smith

Thomas Smith
  • Basic Members
  • PipPip
  • 35 posts
  • Cinematographer
  • Paris

Posted 18 August 2008 - 09:17 PM

Thanks,
I was worry because I've always feel some flicker on video images.

cheers.
  • 0

#5 John Sprung

John Sprung
  • Sustaining Members
  • 4635 posts
  • Other

Posted 19 August 2008 - 12:10 PM

CRI and flicker are completely separate issues.

CRI is a subjective measure of how closely human vision perceives the color of flourescents matching Planckian sources such as incandescents and the sun. It doesn't mean much as far as film or video color is concerned. Operating temperature can vary the amount of energy in the 546.1 nm green spike, so a flourescent may photograph greener as it warms up.

Flicker happens when you have a beat frequency between twice the power line frequency, which is the flourescent pulse rate, and your frame or field rate.




-- J.S.
  • 0


CineTape

Broadcast Solutions Inc

Gamma Ray Digital Inc

Paralinx LLC

Wooden Camera

Rig Wheels Passport

Visual Products

Media Blackout - Custom Cables and AKS

rebotnix Technologies

FJS International, LLC

Technodolly

Metropolis Post

New Pro Video - New and Used Equipment

Willys Widgets

Abel Cine

Tai Audio

CineLab

Ritter Battery

The Slider

Glidecam

Aerial Filmworks

CineTape

Gamma Ray Digital Inc

Broadcast Solutions Inc

FJS International, LLC

Technodolly

Ritter Battery

Rig Wheels Passport

Wooden Camera

New Pro Video - New and Used Equipment

Media Blackout - Custom Cables and AKS

CineLab

Willys Widgets

Abel Cine

rebotnix Technologies

Aerial Filmworks

Paralinx LLC

Glidecam

Visual Products

Tai Audio

Metropolis Post

The Slider