It’s a pity that the Sony A7s can’t do 4K 4:2:0 direct to SD card for ultra-compact 4K full frame; video pros won’t care, but speaking as a non-pro video “interested user”, 4K video is great stuff, and doesn’t have to be an indie film to be useful and enjoyable. I’d prefer in-camera 4K like the Panasonic GH4.
Looks like the Atomos Shogun is a good option for what Sony A7s users will want for recording 4K video and similar. About $1995, coming in September. As far as I can tell, buyer supplies the HDD or SSD drives for the unit (no drives included). One might for example install single or dual OWC Mercury Electra 960GB SSDs. Reader Eric W also suggests the Odyssey 7Q, at about $2295.
The new Atomos Shogun is the world’s first 12G SDI & 4K HDMI I/O monitor/recorder/deck and features a stunning 1920×1200 SuperAtom IPS 7″ touchscreen with 325 PPI, 179-degree viewing and 400nit brightness and multi-frequency (48/50/60Hz) operation (depending on video input) giving it super-smooth monitoring and playback.
The Shogun utilizes both 4K and HD clean output from HDMI cameras such as the latest Sony A7S and Panasonic GH4 and 4K SDI Canon C500. It can record 24, 25 or 30p from the camera and up to 120fps regular HD if the camera is capable. It also has genlock in for synced playout and features optional Wifi for remote control from iOS or Android devices. Improved audio handling with the included Lemo breakout cable for XLR Audio gives balanced audio, mic and Phantom power.
Like the Samurai and Ninja Blade, Shogun allows you to set up the shot with waveform and monitor assist tools, record pristine 422 10-bit images straight from the camera sensor directly, all to inexpensive single SSDs or RAIDed HDDs, captured using 4K/HD ProRes, Uncompressed RAW Cinema DNG or Avid DNxHD codecs.