We shot the video, encountering only a few setbacks, thankfully. I might delve deeper into the specifics of making TERRESTRIA in another post, so for now I'll leave the tales of tornadoes and tears for later. The Panasonic functioned beautifully throughout the shoot, and I think I only had to swap the batteries twice the whole time. The flip-out screen was hugely helpful in lieu of any external monitor, and the focus peaking was a very welcome change from the eyeballing-and-hoping method of keeping focus I was used to with the Canon 5D Mark III. Neither of these features were surprises, obviously, but I found myself relying on them quite heavily.
The biggest unexpected plus from the GH4 -- something I must have overlooked/under-anticipated in my research -- was the quality of the 1080p 60fps footage, recorded at 200mbps. I have a huge fondness for the 60fps framerate, as I think it has a lovely look when interpreted at 24fps. It graded tremendously well and just looked fantastic with the slightly-customized Cine D color profile I used for much of the shoot. I ended up scrapping all of my 96fps footage, save for one shot that made it into the final cut. Like others have said, when you crank up the VFR settings that high, you really have to be in optimal conditions for it to look as good as the rest of your footage. Also, 96fps is just too much for what I was filming; slowing down the 60fps footage was perfectly fine for what I was trying to achieve.
Since I was filming in June 2015, I didn't have the recent V-Log firmware update, which seems to be getting a mostly-positive response from what I can tell. I was perfectly happy with the Cine D and Cine V profiles included on the base firmware, but if I were to purchase a camera I'd look more closely at the logarithmic profiles available across brands.
All-in-all, I loved the GH4. It was perfect for what I was trying to shoot, which is probably the highest praise someone could give a camera. I don't know if I'd buy one; the lack of built-in ND filters, no XLR input without a costly adaptor, and the more general drawbacks of the Micro Four Thirds sensor would push me towards a dedicated video-oriented camera body, but it fit my needs exactly for those five days in June. [Side note: I'm not actually as down on the Micro Four Thirds sensor as many others out there seem to be; I enjoy the aesthetic and the noise issue isn't nearly as bad as people are saying. The lens options for m4/3 are ever-expanding and there are already some great lenses out there: the Veydra Mini Primes are fast and sharp and flare nicely as well as being fully manual. I'd probably opt for a full-frame sensor myself, but there's nothing wrong with Micro Four Thirds. Calm down, everybody.]
Yikes, this is getting lengthy. Anyway, the circumstances in which I used the a7S were vastly different from when I shot TERRESTRIA. A friend of mine was going to be visiting for a few days from LA, and we decided we should shoot something quick while he was in town. We threw ideas back and forth for a while and eventually worked out a script we could shoot over two nights that would cost as little as possible. When it came time to place the order (we had an even smaller budget for this project) we found out our other friend who had agreed to act could only help out for one night. After a moment of panic, we decided to charge ahead and shoot it all in one night anyway, a decision only reckless idiots like ourselves could make.
With fewer hands on deck than TERRESTRIA, (we had a two-person crew: I was running the camera/acting in part of it and a fourth friend running sound) three times the cast, (admittedly, TERERESTRIA only has one character) half as much equipment, (we had to beg around for a shoulder rig and LED panel) a much stronger need for on-location sound, and only one night to shoot it all, we were in for a rough night. Surprisingly, we got all the shots we wanted and most of them were even usable. Our sound levels were low across the board but definitely salvageable, so I was caught in a near-constant relieved sigh as I edited together our poorly-conceived creation.
As for the a7S, it functioned... as expected. I knew battery life was going to be a big concern, but we were going to be near electrical outlets for most of the shoot so we weren't in dire straits.