@Vesku it's true it's hard to compare the GH4 and the GX85, but my impression is that both the G7 and GX85 are just incrementally better than the GH4--a small but significant difference, but small enough that it isn't a big deal.

How bad is the GX85 in-camera audio? This video compares the audio track from the camera to that from a Zoom H1 (with dead cat) recorded at an outdoors opera recital, with full orchestra. The concert sound was, of course, amplified, so mic placement is not the issue. What is the issue is wind noise and compression (AGC and the low audio bitrate (128 kbps). The H1 soundtrack is 24 bit, 48Hz and uncompressed (1560 kbps). The first clip is with in-camera audio; the second is the same clip with the H1 audio:

You will note that the H1 track is at a lower level; that is because it has the full dynamic range (the peak is -1.0 Db) while the in-camera audio is pumped up and leveled In-camera). How bad is the GX85 audio? Real bad.

Can someone enlighten me why using a 64gb card AVC 1080 30P shows a recording time of 5h 43m and MP4 is 27m 09s while MP4 2160 30P is 1h 22m. Are the the non 4K modes still limited to 29m 59s (hint 720 30P is 29m 59s)? Also any opinions on which is better for 1080 MP4 or AVC and why?

Finally got some time to get out and shoot... I'm liking this kit much better than the GH4 despite the audio handicap.

Here is what I do - A Zoom H1 with an XLR adaptor lets you get a clean audio mix straight from the soundboard - its invaluable for concerts and speeches - and you get to have a nice chat with the sound guy as you try to convince him to let you plug in. Having a live mic (as you did) for audience interaction (applause mostly) and ambient is nice for the final sound mix.

GX85 may be mediocre but I think GH4 internal sound is quite good. Uncompressed 16bit 1500 kbits/s, no noise at all. I have recorded some concerts and listened with big surround system. The athmosphere and sound clarity is good and I can think being in the concert when listening. I also recorded an airshow where the F18 hornet went at near distance with after burners (very loud) and the sound was very realistic when listened at home. I have a home made foam cover in internal microphone so that the wind noise is minimal outdoors. The only issue is to record someone speaking when not near the camera.

When using a good mono mic we loose the atmosphere or stereo effect. It would be nice if the camera would have an internal mixer mixing external mono mic and internal stereo sound.

Here is my current foam. It had a second layer of rough foam and it was more effective.

@markr041 It has become pretty clear that wind, in camera stabilization and internal mics are not a good match. Which really presses the point of how important it is to include a mic port so you can get the mic isolated from the camera body and put foam or deadcat on the mic. You would have thought this was a great opportunity for Panasonic to sell there own external mic to non pros. Confront the issue and offer the solution. Hell they could have left the mic off all together and offered a sound kit that plugs in to camera. Instant secondary revenue stream could look something like the Tascam DR-10SG. Even with the sound issue I still love what's good about this camera till something better comes along. Just a heads up I wouldn't expect the GH5 to be immune to the same stabilization noise issue!

@scot I agree with you on the need for separate mic and wind protection. And I am surprised too that Panasonic omitted the mic input or having a hot shoe mic (and also manual audio controls). They really were protecting their higher-level cameras. @Vesku I agree that the GH4 has good audio; one reason is you can control levels manually (turn off AGC). It is also clear that they cared about audio quality for that camera.

For fun, here is the H1 audio track used in the intro cut from the opera video:

http://ugofoto.blogspot.ru/2016/08/panasonic-gx80-impressioni-di-uso.html

Some image related observations that may help in your shooting:

I originally shot with Natural Mode a lot, and shifted to Standard a few weeks ago. I haven't been super happy with either mode when it comes to higher ISO's, but in testing earlier this week I discovered that PORTRAIT mode looks great at higher (and lower) ISO's with less visible noise reduction at work, and it has a smoother fall off between dark and light areas. The higher iso grain on this setting is fine and very filmic.

Test it out and compare to Standard/Natural. I'm only using Portrait mode from now on with these settings.

-5, -5, -5, -3.