Radup, sorry for the late reply, I missed your questions
Yes, the ballon starts at about 1m in diameter, then lowly expands as air becomes thinner and explodes when the diameter reaches 7-8 meters.
The system has a small parachute, the descent wasn't as smooth as planned (the fragments of the ballon were garbled in the parachute) but yes, the camera is still usable :-)
