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Magnetic Ballast Question- film/video


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#1 monster vs robot

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Posted 27 March 2006 - 11:13 PM

Hi All,
I was wondering if anyone could help clarify a few things. I just bought 3 older LTM Luxarc HMI Fresnels. Great old units in excellent condition. 2 1200's and a 2500. These are the ones with the old connectors on the head feeder and ballasts that weigh a ton. My recollection is that I should be ok using these with a non-crystal camera, but has anyone experienced/foretell of any flicker problems with video @24P or with the hvx 200 overcranked? Any help is appreciated.
Pierre
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#2 David Mullen ASC

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Posted 27 March 2006 - 11:56 PM

No, you DO need to use a crystal-sync camera running at HMI safe speeds when using magnetic ballasts.

24P (23.98P in most cameras actually) usually handles magnetic ballast HMI's & flos fine, although some people say you can see a subtle exposure fluctuation on a waveform. But I haven't had any problems, but even if you did, you can use the electronic shutter on most video cameras to match the lights better, like by shooting at 1/60th for 60 hz lights.
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#3 monster vs robot

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Posted 28 March 2006 - 12:46 AM

No, you DO need to use a crystal-sync camera running at HMI safe speeds when using magnetic ballasts.

24P (23.98P in most cameras actually) usually handles magnetic ballast HMI's & flos fine, although some people say you can see a subtle exposure fluctuation on a waveform. But I haven't had any problems, but even if you did, you can use the electronic shutter on most video cameras to match the lights better, like by shooting at 1/60th for 60 hz lights.


David,
Thanks. I was hoping you might catch this one for me. I really appreciate it!
pierre
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