In the words of Philip Bloom. "Let's get this straight, quad HD isn't 4k. (Talking about bmcc)" but it applies here too. A7s does a full frame UHD video, not DCI 4k like the gh4... Unless I missed something in the spec sheet.
And you are looking at the A7s + atomos for $4k to get any sort of 4k ability. And $2k for gh4 with internal 4k.
Anyways... The copy.com link that doesn't work is this "https://www.copy.com/browse/copy/GH4" that's your URL link. You need to get the "share" link for the folder containing the files and post that.
DIrector Bob reacted to JonnyGinese in Panasonic GH4 Production Diary - Day 4 - Low light