Take a 140+ m rope, fold in half such that there's a loop. Affix a sizeable weight near the loop such that it is stationary on one side of the rope and the other side moves freely through the weight. Lower the loop down such that it is positioned, open, at the dog's level (like a snare). Wait for the dog to walk through the loop such that front paws are on one side and back paws on the other (obviously need a camera down there). Raise and tighten the loop (by pulling the length of rope that is free moving through the weight) such that the rope closes snugly around the dog (i.e. over its back and under its front legs; NOT around it's neck obviously). Raise.

Edit: diagram: http://imgur.com/a/W8PZ6