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25p in 60 Hz country


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#1 Bernhard Walzl

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Posted 08 November 2018 - 03:44 PM

G'day,

In my country we use European standards for TV production (PAL) however, power is running on 220V / 60Hz.

 

In order to minimize flickering effects, I shoot most of my productions NTSC. (I shoot usually 30p or 60p)

 

We recently produced a short film and got the chance to screen it on a big screen at a local cinema. To my great disappointment I had to watch the film with very noticeable stutter. I guess the projector was running 25p but my film was 30p and therefore images got dropped creating the jerking effect.

 

So this is a big problem and I need to find a solution. I tried on a Canon 5D III to swap over to PAL (25p) and used a shutter speed of 1/60 but there was still very strong noticeable flicker.

 

What would you folks do in such a case? I have been told newer cameras have an anti flicker option but I just don't like using such electronic filters during principal photography.

 

Let me know what you think,

Bernhard

 

 


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#2 David Mullen ASC

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Posted 08 November 2018 - 05:04 PM

Using a 1/60th shutter should have solved the 60Hz flicker problems from AC discharge lamps and ordinary fluorescents.


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#3 Bruce Greene

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Posted 08 November 2018 - 06:26 PM

For all world release, I would shoot at 24fps.  Add conventional 3:2 pulldown to make a 30fps version. Speed up to 25 fps for a PAL or European TV release.  DCP standard is 24 fps almost everywhere for cinemas.  When shooting in 60 HZ countries, have the shutter at 1/48th sec.  In 50 HZ countries, 1/50th sec.  I think in shutter degrees it comes out to 180d for 60 hz, and 172.8d for 50 hz.

 

I've been shooting in Europe for theatrical cinema release and we always shoot 24fps.  The project is sped up to 25fps for TV release.  I suspect your jerky projection was caused by conversion to 24fps, not 25fps.


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#4 David Mullen ASC

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Posted 08 November 2018 - 06:45 PM

Are we talking about flicker from pulsing 60 Hz AC discharge lighting sources or projector motion judder, stutter, etc.?


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#5 Bruce Greene

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Posted 08 November 2018 - 07:04 PM

Are we talking about flicker from pulsing 60 Hz AC discharge lighting sources or projector motion judder, stutter, etc.?

I was assuming both.  He shot 30/60fps to avoid lighting flicker, and then projected at 24fps and saw the jerky projection from the dropped frames.


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#6 Robin R Probyn

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Posted 08 November 2018 - 08:23 PM

If its light flicker just use your shutter.. I live in a country with the opposite..NTSC TV the whole country but both 50Hz AND 60 Hz regions.. ! and I have to shoot 23.98/25/29.97/50/60/100/120/150/180... the whole nine yards !.. shutter is the way to get rid of flicker from most light sources .. what ever is divisible by the mains cycle ..  for 23.98/24 I would use 1/60th in 60Hz regions rather than 1/48th..

 

For slo mo.. eg 100fps for the 50Hz regions.. 120fps for the 60 Hz..  50fps /50Hz.   60 fps /60 Hz..

 

If your looking to have your stuff shown at cinemas and TV.. then shoot everything 23.98p.. 1/60th shutter..


Edited by Robin R Probyn, 08 November 2018 - 08:27 PM.

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#7 Bernhard Walzl

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Posted 09 November 2018 - 12:06 PM

Thanks for your answers!

 

Thats correct, I have used 60p to get rid of lighting flicker. And the motion stutter was due to the conversion from 30p to 25/24p.

 

 

Well the thing is I have tried on a Canon 5D III to shoot PAL with a shutter speed of 1/60 to get rid of the lighting flicker but the results were not good and only switching over to NTSC eliminated the problem.

 

 

Well, it's a bit of a broad question but having now 30p footage in my hands, what is the best way to convert this to 25p/24p? Is there anything smarter to do than just export the footage using 25p?

 

Cheers,

Bernhard


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#8 David Mullen ASC

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Posted 09 November 2018 - 05:23 PM

It shouldn’t have made a difference, 24 fps vs 25 fps vs 30 fps — all the 60hz lights care about is shutter time. Perhaps the camera didn’t actually implement the 1/60th setting.
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#9 David Mullen ASC

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Posted 09 November 2018 - 05:24 PM

If you don’t need the motion to be normal speed, then the best method is to just play the 30P footage at 24 or 25 fps, slightly slow-motion.
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#10 Robin R Probyn

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Posted 10 November 2018 - 09:45 AM

"Well the thing is I have tried on a Canon 5D III to shoot PAL with a shutter speed of 1/60 to get rid of the lighting flicker but the results were not good and only switching over to NTSC eliminated the problem."

 

!/.50th or 1/60th shutter.. no one in the world would know the difference .. at 30p..  I think something is wrong with your setting sir..

 

Dont change the frame rate to get rid of light fixture flicker .. just the shutter speed/angle.. 


Edited by Robin R Probyn, 10 November 2018 - 09:47 AM.

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