How good is RX100 video quality?

I also use Portrait...it's a very flat color profile that is perfect for grading.  If you don't intend to do any post work then Sunset is also great if you manage to adjust the white balance on each shot to get rid of the warmth in the image.  Normal is fine too, but to get the best out of the video shoot neutral in portrait with everything turned down to -3 (maybe color at -1 or -2) then adjust color temp, sat, contrast, black and white levels, sharpness, etc. in post.

Oh and for audio I'm sure it's ok to use the onboard audio in a pinch but I wouldn't bother for anything serious, use a Rhode or Zoom or any external audio recorder.  There's even a new Zoom mic for iPhones that should work really well.  I like using it on a pistol grip rig or handheld (or on my Phantom now!) because the stabilization is amazing.

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