How do I prevent flickering when shooting iphone video with fluorescent lights?

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Level 1

14 points

How do I prevent flickering when shooting iphone video with fluorescent lights?

So I have been using my iPhone 7 to shoot myself against a green screen lit by two softboxes with CFL (fluorescent) bulbs -- and once I import the video into Final Cut Pro X, I find there is a fair amount of flickering. Please note that the lights do not seem to be flickering at all while I'm shooting. Can someone please tell me what adjustments to make to avoid the flashing/flickering light? I'm interested in multiple solutions, so if you see that someone else has answered, I'd still value your advice, as well. Thank you.

iPhone 7, iOS 11.2.1

Posted on Dec 13, 2017 7:40 PM

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Answer 1

Best reply

Meg The Dog

Level 6

13,561 points

Dec 16, 2017 3:15 PM in response to Womanhattan

Flickering is often a result of the desynchronization between the shutter speed/frame rate of the camera and the frequency of the AC power that the lights are plugged in to.

A solution is to use a shutter speed/frame rate that is slower than the frequency of the AC power.

For example, in the U.S. the AC power is 60 cycles per second, so try shooting at frame rate less than that - 30 fps, 29.97 fps, 24 fps, 23.98 fps - and a shutter speed that is slower than the AC power frequency.

Note that the camera app that comes with the iPhone uses shutter speed to control the exposure. You will want to be using a more sophisticated video camera app for your recordings that give you more control - to lock down shutter speed, etc. Two good choices are Filmic Pro and MoviePro.

MtD

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Answer 2

Womanhattan Author

Level 1

14 points

Dec 16, 2017 3:30 PM in response to Meg The Dog

Based on my description of "flickering," it seems this would be a very helpful response, and I thank you! However, I'm realizing that what I experienced should have been described as random changes in the light -- almost as though my bright lights shut off just in certain frames (though the lights were, in fact, on continuously). I resolved this issue simply by touching the iPhone screen until a slider appeared that let me adjust and lock the exposure. I did take your advice and download an app, which I'm sure also would have resolved things, but it seemed a bit less simple than I like things to be. Either way, my problem is solved -- and just your mention of exposure and shutter speed led me to it : )

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