In regards to what cameras this is comptabile with, the hack author notes:
This app should be compatible with all Sony cameras supporting PlayMemories Camera Apps.
The risk is your own of course if you use such hacks and make sure you understand what you’re getting into.
Users are reporting getting 90 minutes on the Sony A7s II, over an hour on the Sony A7r II and the Sony A6300 and over 2.5 hours on the Sony RX10-II, for example.
apertus is the open source cinema group whose stated goal is:
to create a variety of powerful, free (in terms of liberty) and open cinema tools that we as filmmakers love to use.
apertus have partnered with the good folks from Magic Lantern who are known for their modifications to Canon DSLR’s firmware to liberate new features (such as raw video, amongst other revolutionary changes).
AXIOM Beta is a brand new professional digital image capturing platform and the crowd funding backers get access to it before anybody else does.
AXIOM Beta is a 4K Raw camera available in a few different configurations.
Progress is being made and now the first image date has been captured from the sensor:
To read more about this, read apertus’s blog post: Axiom Beta: Hello World
Don’t hold your breath for 5K video from a Nikon DSLR as 12 bit 1664 x 1100 resolution is what is provided right now. But the live-view stream is 4992 x 3280 pixels and it should be available to be captured. Even if live-view is captured, it would likely be at a lower frame rate than 24fps.
When the Magic Lantern team first started capturing live-view on Canon cameras they were not sure what they could do with it but they quickly made it into very useable frame rates. So it will be interesting to see how this development goes.
You can view the thread about this raw video hack on the Nikon Hackers forum and below is a raw frame example of what they have done so far.