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A possible simple fix for flickering slow-motion video

With the transition to LED lighting, I was hopeful it meant the end of flicker in slow-motion videos, because LEDs don't heat-and-cool the way an incandescent bulb does when running on AC power. Alas, after installing some EcoSmart 100W LEDs over our pool table, I was still getting horrendously bad flicker in my iPhone slow motion videos.

I did a bunch of web searching, and most of what I read said that I'd need to find a way to run the lights on DC, or change my frame rate, in order to avoid the flicker effect. Neither was really a viable solution.

Then, on a lark, I searched Amazon for 100w no flicker LED bulbs, which returned a ton of matches—most of which weren't applicable (I didn't need a 16-pack, and they had to be normal-style bulbs). But I did eventually find the LOHAS 100W Equivalent LED A19 Light Bulbs, which promised "Non-flickering light and zero harsh glares."

I ordered a box (four lights), replaced my existing lights…and surprisingly to me, the new bulbs eliminated the flicker—based on what I'd read, I didn't think there was much of a chance that a simple bulb change would work. But it did.

This short video shows the difference between the EcoSmarts and the LOHAS.

Warning: There is some serious flicker in the first part of this video.
Do not click Play if such things affect you!

You can still see a tiny bit of flicker, but it's nearly imperceptible. And a short "stop shot" test video I made seems entirely flicker-free to my eye:

Based on this experience, if I ever have to replace any of our other LED bulbs, I'm going to make sure I look for bulbs that state they're flicker free.

2 Comments

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  1. LED lights have to convert AC to DC internally: Because diodes only pass current in one direction, if it didn't convert to DC, the flicker would be much worse. It's a lot more expensive to design a circuit that does it well - the most basic circuit, (a bridge rectifier), gives you a 'bouncing-ball' voltage, which would flicker even worse than an incandescent.

    Doing that with electronics inside the lightbulb means it has to survive wide temperature changes from room temperature to its nearly 200-degree operating temperature, in a small package, yet be cheap enough to be disposable when the bulb fails.

    It's too bad the bulbs you found aren't dimmable.

    1. Thanks for the detailed explanation…and yea, dimmable would be nice in general, but not required for the pool table :).

      -rob.

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