Why do I have a slight flickering while shooting with my Canon t3i?

[coolhandluke67]

I have a canon T3i, I shoot 30 frames per second at 1920-1080. I have a 64GB SD card that does 70mb per second.

Now lately I have noticed that sometimes while shooting there is a little bit of a flicker that occures.  It will flicker once, and not do it for awhile, and other times it will flicker in a row for awhile like every other second and then stop. It is not a strong flicker, it is more like a small color jumps from dark to light. Btw I assure you that all of our lighting remains steady and that we dont make much movement (its a talkshow type of thing).

I also would like to say that we have it on manuel focus so I dont think it is a focus problem. But I tried it also on autofocus, but with no luck as well. One thing we found that made a difference was that when only one of us was in the shot the flickering did not occur. I am unsure what is happening. Also the longer we shot the worse it got it felt like.

Hope someone knows what the problem is. Also would like to point out that I am a beginner so if you explain something please do it in detail so I understand exactly what to do. Thanks a lot!

[kvbarkley]

What kind of lights are you using? If you are using flourescents, they have a known flicker problem. Try outside in the sun or shade.

[coolhandluke67]

Its not florescent. They are incandescent light bulbs running at 60 watts. I see no flicker visually. Only on the camera.

[coolhandluke67]

Here is a video so you can see exactly what I mean

https://www.dropbox.com/s/dg3bg704kltqf53/cut%20version.mp4?dl=0

[Waddizzle]

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@coolhandluke67 wrote:

Here is a video so you can see exactly what I mean

https://www.dropbox.com/s/dg3bg704kltqf53/cut%20version.mp4?dl=0

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For whatever reason, my Windows 7 Pro machine cannot play your MP4 file.  WMP reports that it cannot read the format.  Maybe I can try it later on one of my other machines.

Have you tried to shoot video outdoors, yet, to see if the flickering problem persists?  Have you tried to shoot video with Auto Focus and Image Stabilization on your lenses turned off, to see if the flickering problem goes away?

[Peter]

Do you use AWB?

[coolhandluke67]

Yes I set my own white balance awhile ago.