I am confused with a few things. I am wanting to purchase a copter capable of carrying a GH4 camera but using a Pixhawk. Here are the things my googling has failed to answer for me:

1. Is there a Pixhawk-based platform equivellant to the DJI S900? I have pretty much determined that is the predominate solution for what I want to do but I do not want to run A2.

2. What Gimbal works with the Pixhawk that is built for the GH4?

3. The Zenmuse Z15-GH4 seems to be the dominate gimbal but only works with the DJI flight controller(s). What exactly does the flight controller do for the gimbal? Isn't the gimbal independently controlled or can you tie it into your flight planning somehow?

Any guidance would be appreciated, thanks!

Matt