Why is depth of field different in live view vs. video recording on my Canon 5D?

Question

I recently got a Canon 5DmkII.

This weekend I was at the local high school football field playing with the camera and recording video. I set the camera down on the field, turned live view on, and pressed the focus button in order to focus on a soccer ball. In the live view, the depth of field was amazing. I was so excited to record. When I pressed the center button to record all of sudden the depth of field changed. It was not even close to what it looked like during in the live view before recording.

Why is this?

Answer

Usually, LiveView is shot with the aperture wide open, hence minimum DoF. When actually shooting (or recording), the aperture closes down to whatever your setting is. Try setting to max aperture to record what liveview sees.

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