Yes, aware of that, and nothing recent works with it, the last progress sadly was years ago.

I guess DMCA/Sony Lawyers and the relatively low market share for expensive cameras is the main reason why a PlayStation, an iPhone or a Nintendo Jailbreak is more appealing to reverse engineers than a Sony Camera Jailbreak.

Actually, half of the problem is vertical integration inside Sony cameras. It's all Sony from sensors to DSPs, and everything is designed and built by them.

The current firmware looks like a embedded Linux system designed for fast boot and is largely immutable, so the thing is pretty tightly secured down. You can put the board to flash mode and update the firmware, but that's all apparently.

Someone over DPReview was taking deltas of the file trees between firmware update packages to guess what has been updated, but going one step further was nigh impossible.

Sony doesn't even bin the DSPs from model to model, but create model-specific ones with different model numbers, and solder DRAM on top of them for latency and signal quality, so the cameras are complete black boxes.

The only missing thing is a complete epoxy pour over the board, but that thing gets hot and needs the case as a heat-sink, so it's not possible at this stage.

The other half of the problem is what to gain from a root shell. You can't influence the stages of the image processing without a PhD in Sony DSP Reverse Engineering, and so what remains is probably hooking into the camera controls and injecting key events to re-invent time-lapse timers or bulb exposures, and removing the 30min video recording limit.

This is where the NX mod project arrived - additional hooks into the camera controls and a few changes to internal registers left over by Samsung engineers for debugging, like silent shutter or the 30min limit.

Sony's full frame machines are so customizable out of the box already, so you don't need anything to begin with, at least for normal photography needs. Maybe focus stacking, but it's a pure new procedure.

30 minute recording limit is already lifted and advanced time-lapse is introduced alongside mammal eye tracking with a firmware update by Sony, and you can customize anything sans preliminary image processing steps, and by customization I mean the parameters of the algorithms or algorithms themselves.

Moreover, Sony's full-frame systems are already distributed systems to begin with. There are at least two DSPs running asynchronously during focus and image capture, so there may be no pathways to influence the DSPs significantly after they boot up, even.

Personally I wouldn't muck with a system designed to do image processing 30FPS even before taking a photo (A7-III) incl. face and eye tracking and focus correction without any hiccups to this day.

From what I understood, these cameras perform a nigh impossible dance within the limits of their hardware to maximize speed and reduce energy consumption. Who am I to disrespect them for doing that. Instead, I prefer to use the thing and get nice photos out of it.

I want to write my own metering algorithms in the pursuit of ETTR instead of using the current garbage leftover from film cameras

It works on the stock firmware of the FX30, which is relatively recent.