A7x series cameras have only one multi-terminal port, which can as a tethering port, a flash sync port, and a cable release port. The problem is when you want to use two functions at the same time, then you are completely screwed.
I have some application that needs the camera to be connected to a machine and be trigger automatically at certain interval, at the same time tethered to a computer for images to be processed right away. And I can't figure out how to do this with A7r.
Anyone knows how we could get around this at all?
This is a major drawback to this camera. Considering the cost of the camera and that they aimed it at "professionals" it should have included a separate shutter port and flash sync port, or at least offer some sort of "splitter" cable. Even the cheap Rebels have this.
I shoot primarily still life while tethered in the studio, and often use an automated Stackshot system, or laser triggering Stopshot system for shooting liquids/splashes.
When I first got the camera I spent several weeks trying to figure out a way to tether and have hard wired access to the shutter. I went as far as purchasing different multi terminal shutter cables, taking them apart, and soldering the USB leads to a USB cable, but when the camera detects USB power it disables access to the multi port shutter (at least that's what happened in my case).
The best solution I found for using the Stackshot while being tethered was to get one of those cheap infrared remotes, taking it apart, and soldering a cable to the shutter button on the remote. I then removed the infrared bulb and attached it to another cable which I ran in front of the camera to the infrared sensor.
However if I need faster triggering like when shooting liquids with my laser trigger, I have to use the multi port cable, and shoot to an SD card instead of being tethered, which is a huge PITA. There is too much lag latency when using the infrared remote. Hopefully Sony will get their act together and add these ports to their so called "professional" cameras in the future, or at least offer some sort of splitter cable.