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Tips for improving the quality of this video?

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David Watson
Tips for improving the quality of this video?
on Sep 27, 2014 at 2:48:57 am

Hi Everyone,

Just a brief request for any feedback about the quality of this video:
http://integrationkings.wistia.com/medias/qqgww3j882

(Please ignore the spoken content of the video).
I'd like to stop the background flickering, which I find really distracting.
Any tips to improve would be greatly appreciated.

The camera is a Canon 7D shooting HD video 1920x1080 at 30fps.
50mm prime lens was used.

Other camera settings:
Shutter Speed = 1/60
Aperture = f/1.8
ISO = 160

Auto Lighting Optimiser is Disabled.
Highlight Tone priority is also Disabled.

I'm using the lighting setup and technique recommended in the Wistia learning centre.

Thanks for any help!
Dave.


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Steve Crow
Re: Tips for improving the quality of this video?
on Sep 27, 2014 at 9:01:22 pm

I'm thinking that the flickering has to do with the use of fluorescent lighting and the local power supply.

This issue has been talked about many times in this forum but you may also want to check out the following article which includes a handy calculator:

http://www.red.com/learn/red-101/flicker-free-video-tutorial

"The key is that many types of artificial lighting flicker at twice the rate of the power source. This is most pronounced with fluorescent lighting, but also happens to a lesser extent with incandescent. Common power sources are 50 Hz (in Europe and most of Asia) and 60 Hz (in North America), which cause 100 and 120 pulses of light each second, respectively.

Other than changing the lighting, one has two options for overcoming this problem:

Frame Rates. Choose a frame rate equal to the lighting pulse rate divided by some integer. This is often the simplest option since most corresponding shutter speeds will appear flicker-free.

Shutter Speeds. Choose a shutter speed equal to the lighting pulse rate divided by some integer. This option often isn’t as straightforward, and can constrain one’s ability to control motion blur. On the other hand, this option typically minimizes flicker under a broader range of lighting and power types.

For example, in North America, the standard 24 and 30 fps settings work with most shutter speeds (since 30×4 and 24×5 = 120). "


Using the calculator (and I'm assuming you are filming in a UK location based upon the accent) it suggest a 1/50 shutter speed even though I know you were following the 180 degree rule and so selected 1/60.

The other issue aside from the flickering is that the video is about as interesting as a filmed deposition. It's not really about the content which in fact could have been interested but the way it was filmed. The subject is placed dead center, with a very bland gray background and there is no b-roll to cover and illustrate what he is saying, perhaps some music or text effects would have helped too. The lack of these actually draws MORE attention to the flickering.

I think the compression is also causing some slight banding in the background but it's not too bad, perhaps bump up the data rate a bit.

Steve Crow


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Jim Tierney
Re: Tips for improving the quality of this video?
on Sep 30, 2014 at 5:28:06 am

Steve is correct that it's probably an issue with the electric cycle being out of sync with the camera. All types of lights can cause this, but fluorescent and LEDs are the biggest culprits.

As he pointed out, adjusting the frame rate and shutter speed should solve it.

This is another good article on the topic:

http://provideocoalition.com/aadams/story/rolling_shutter_and_flickering_hm...

For footage that can't be reshot, we develop a plugin, Flicker Free, that solves this problem. It works in most hosts: After Effects, Premiere, Resolve, FCP, Avid, etc. You can get more info here:

http://www.digitalanarchy.com/Flicker/main.html

cheers,
Jim Tierney
Digital Anarchy


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