Download the Panasonic Image app for IOS or Android and you have access to most of the camera functions remotely with video preview! You can start and stop recording and switch quality. The delay is very short and you can even preview video and stills remotely too. If you use one of the 2 Panasonic Power Zoom lenses you can zoom remotely.
Editing and ‘magic’ down-conversion
So far I’ve used Grass Valley EDIUS 7.3 for editing the 4K and UHD footage straight from the cameras SD card, Adobe Premiere Pro CC is fine too. In EDIUS I was using a 10bit project with the 8 bit 4K or UHD footage and resampling using Lanczos scaling to create 10bit 4:4:4 HD from the 4k. If you are of the Mac persuasion check out this app http://www.eoshd.com/comments/topic/5426-mac-app-to-resample-gh4-8-bit-420-to-10-bit-444/ Scaling 4K recorded internally in the GH4’s SD card and converting it to HD is an almost magic process which creates 10 bit 4:4:4 colour video files from the 8 bit 4:2:0 originals. It takes the extra resolution of the 4K files and converts it to extra colour resolution in the down-converted files. It even takes down the noise if you have shot at high ISO.
I would recommend that you always shoot 4K with the GH4 unless you need 1080 50p or up to 96fps Variable Frame Rate. The camera uses native pixels for both 4K and UHD which will reduce moiré and aliasing compared with pixel binning for the HD (still much more favourable than line skipping)
Using the native pixels has an impact of the crop factor of the sensor and I would say you get a crop factor of 2 for HD, 2.2 for 4K and 2.3 for UHD.
My favourite lens for the GH4 is the Lumix 12-35 F2.8 constant aperture from Panasonic, it gives a range equivalent to 26 – 77mm on a full frame sensor, which is really useful. It also has stabilisation and fantastic autofocus, and the constant aperture means you can zoom without the aperture changing.
Panasonic don’t quote a base ISO, but as you can set the camera to report Gain or ISO, and seconds or angle for shutter speed, I’m guessing that it’s 800, as this equates to 0db.
As I work for Holdan (a UK, Ireland and European Distributor) I see a LOT of professional camcorders and large sensor systems. In my 30 year’s experience of working with video cameras, I can say with hand on heart that the GH4 is the first camera I would trust for both stills and video.