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Bad flourescent flicker from shutter speed

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Jordan Ledy
Bad flourescent flicker from shutter speed
on Dec 22, 2009 at 5:29:30 am

Hi all,

have this interview where the combination of the shutter speed and the florescent lights is causing a bad flicker effect on the background of the shot. The subject looks all good but the bg distracting for parts of the shot (I noticed it during shooting and tried to aim the camera away from the light, which seemed to help).

Wanted to know if there is a quick and easy fix to this, or if i will have to roto the subject in order to correct the issues with the background.

The shot it handheld and the bg is particularly stable, but could def be motion tracked.

Here is an example:

Thanks in advance, always appreciate help from the folks at creativecow.


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Steve Roberts
Re: Bad flourescent flicker from shutter speed
on Dec 22, 2009 at 1:45:55 pm

Did you search the COW for "fluorescent"?

(note the "uo" spelling.)

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david bogie
Re: Bad flourescent flicker from shutter speed
on Dec 22, 2009 at 2:48:23 pm

Yar, we see this topic often, there's a good backlog of supportive suggestions. I usually recommend AE's Color Stabilizer but you may need something more difficult to manipulate sine your foreground has a different lighting system shining directly on him. The FCP folks often export these troubling scenes as image sequences and run a batch process on all of them in Photoshop.

The results of our shooting situation were difficult to predict unless you had extensive experience with mixed lighting sources and understand mains frequencies. Be aware that fluorescents flicker at mains frequencies but many types of high pressure luminaires such as sodium vapor have their own ballasts and flicker out of synch even with mains. You end up with a scene that cycles from properly white balanced to pink, orange, green, and back to normal. The only ways to get around it ire to add enough light to override the sodium vapors (likely impossible), to shut off the sodiums (often an illegal safety hazard in factories or on shop floors), or to shoot at a shutter speed that covers all of the lights' varying on-off cycles; half of the mains freq. Shooting at 1/20 or 1/30 second causes its own set of issues.


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Jordan Ledy
Re: Bad flourescent flicker from shutter speed
on Dec 22, 2009 at 6:05:41 pm

ahh! sorry i can't spell! Thanks guys!

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