In article ,
John Williamson wrote:
I'm not convinced that would be a problem with tungsten lighting
anyway. Large filament tungsten takes ages to react to any change in
voltage. If it reacted to an AC sine wave by switching on and off lots
of humans would see it - as happens with fast reacting lights like
some type of fluorescents.

I'm not so sure about that. I've worked on film sets where the
generators were switchable to 48, 50 or 60Hz.

I can't see even the advertising guys bothering with that unless it made
a difference. Then again, I've seen a lot of discharge lamps on film
sets.

I'm not well up on the types of lighting used on real film.

BBC studios at the time in question were virtually pure tungsten. Only
common discharge type was the CSI follow spot.

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*Verbs HAS to agree with their subjects *

Dave Plowman London SW
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