Two Hero 4's in the GoPro Duo case. No genlock, so all (audio-based) synching is done in post (using a clicker to get audio spikes).

The Black 4's enable shooting at 2.7K at 60 fps. These videos were shot using that setting (medium POV), and edited in Sony Vegas Pro 13. The videos were rendered at 1080 60p sbs and uploaded to Youtube. You can view the 3D 1080 60p version if you use the Chrome browser; otherwise it will be 1080 30p:

https://youtu.be/0RiH_Rbm6Ic

https://youtu.be/peSy00J-ikk

https://youtu.be/_ozZlprKoMY

https://youtu.be/K0SHxK4gzCc

https://youtu.be/0r_Dk9vZGV4

Great. I use 2 Black 3+.
The cams was parallel right? Because everything is in front of the screen.
You have to push it back with horizontal shifting (and loose some resolution),
or shoot a little toe-in.

You shouldn't vary the 3d depth by adjusting toe in, as that will start to produce greater divergence in more distant objects. It will then cause viewing discomfort where the viewer will have to strain their eyes to try to resolve depth in the near and distant objects.

Toe in can be used to help maintain focus on a specific subject when the more distant ones can be sometimes be defocussed so as not to cause retinal rivalry. It is far easier though, to keep the camera lenses parallel and adjust the stereo depth in software, so that the nearest past of the stereo window either coincides with the edge of the viewing screen or is slightly pushed back. If you want part of the scene to appear to be infront of the viewing screen, such as in some of the old 3d films, there are certain rules that need to be followed to avoid making viewing uncomfortable and giving your viewers a headache.

It's also worth remembering that the greater the lens separation, the greater the apparent depth, but the more disparity between near and far objects and the easier it is to get it very wrong.

Framing and distance of objects from the cameras needs a lot more planning and care in filming than with 2d filming, but is very rewarding when you get it right, especially when you are a 3d nut like me :-)

Roger