Yes, I get the "wierd stuff" when the motor is running - MP Jett brushless, Lipo, etc in a Thunder Tiger Sparky. (so I just take pictures in a glide )

Try wrapping some aluminum foil around all your power wires, including battery and motor leads. That should shield it enough to make it work.
You can also try, if you have room in the plane, to seperate the camera from anything with power - in other words, move them away from each other.

Good luck!