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Fluorescent flicker free solution?


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So I'm designing the light for a permentant set outside the windows. And I'd love to have 8ft tubes outside each one. LED or flourecent. Its a tungsten studio, so the tubes would be 4000-4300k.

I was advised by the local grip shop not to use kino flo ballasts because of parts and reliability over the long term, and instead look at permanent housings with Duro-test or Kino tubes.

My concern is flicker or banding with commercial ballasts. Suggestions are appreciated.

On the LED end, I've tested a home depot LED 8ft fixture. Green shift was minimal and it was at 4000k. At 30/60p it was fine, but 24/48/96p it was unusable. The goal is to be safe to to 100-120fps.

I don't mind swapping ballasts, but I don't know if its the simple case of swapping it out with a high frequency, or a specific frequency. And so any help would be appreciated.

No... Purchasing skypannels isn't an option, for those interested.

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In terms of designing a permanent set, with the goal of it lasting years to come and it being capable to adapt to multiple camera packages store bought commercial LED's are probably not going to be your friend.

Flicker, a more quantifiable issue is more easily overcome in terms of just finding an LED fixture with a fast, consistent frequency that aligns with your frame-rates. However, colour shifts and spectral content is a variable dependent on another variable, your camera package. 

From my understanding only quite expensive fixtures designed for superior spectral content (in terms of RGB LED's) or again white light fixtures designed with spectral content in mind would be suitable for this kind of set-up. 

I know aperture made a bunch of discontinued 3200k 'white light' LED's. I've never used or tested them but that may be an interesting avenue to explore! I imagine they wouldn't be too expensive now. (The only reason I recommend them as logic would dictate they've taken a higher frequency band LED and used a strong fluorescent phosphor to emit a wide even frequency band, as a single phosphor LED typically has more spectral content). 

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I considered obsolete aputure. But I'm building a quote and can't lean on the unreliable avenue of finding all materials second hand. And then there's replacements.

Judging from the response, it seems that nobody else has gone through this avenue. Looks like I'll have to source spectrally accurate LEDs, either raw or in tube form, and solve the flicker myself with a 3rd party PWM driver. Or go with cinema florescent and high frequency ballasts.

Exciting!

I'll return with my findings.

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