I've hacked it at 100mb/s !
Footage is simply amazing. Arri Alexa like.
Caution: do not install the Pana official firware. I had to removed it to the original firmware and then hack.
In higher isos more than 1600 (now enabled no isos limits), instead of the sort of soupish undefined dots you got film grain like.
No need to say that lower isos are impressive and ultra-clean.
Clips less highlights too.
BUT
there are also some downsides, as always.
-1) files are huge. 30 sec in normal gh2 is 50M, with the hacked it's 270M
That means SD cards will be filled in 40ish minutes and storage will be more costly.
That's really the biggest problem of the powerfull hacks.
I think I may reduced to a lower bit-rate and find a comnpromise because the workflow will be slower or I'd need soon a proper server installation.
-2) from 6400 isos and above, in some parts of the footage, not always, ( I've noticed that it shows-up in underexposure cases),
appears a "banding". Not quite the same as the banding causes by electrical frequency, just one or 2 fixed bands.
It does not appears at lower isos than 6400. Even at 6400, this banding disappear immediatly if you expose more. So it's only in under-exposures and not always. Weired.
and I wonder what could it be.
I've just done it and if I see more issues, I'll report here.