Fluorescents AND HMI

[4knewave]

Two questions about crystal sync motors.

1. If your shooting under regular fluorescent's (no kino's or ballast to maintain current) on film with a crystal sync motor will they still flicker?

2. When running HMI's, again if your using a flicker free ballast can you use any type of generator as long as it runs 60hz? Or do you need like a crystal sync one.

Thanks

 

[David Mullen ASC]

1. You have to shoot at "safe" speeds. There are charts for that -- search under "HMI safe shooting speeds" or "safe speeds for 60 Hz lighting" or something. 24 fps is safe at crystal.

2. That's a good question that recently came up on Cinematography.Com and no one had a definitive answer. The rough consensus was that if the non-crystal generator drifts too much in frequency, the ballast would have a hard time correcting for that and you could fry it, so probably a rental house would not recommend you try it.