 Due to their low weight and the fact that they had only one control wire per leg , the puppets were unable to walk convincingly . Therefore , scenes involving movement were filmed from the waist up , with a puppeteer holding the legs below the level of the camera and using a " <unk> " action to simulate motion . Alternatively , dynamic shots were eliminated altogether : in an interview with New <unk> , director of photography John Read spoke of the advantages of <unk> the lack of agility so that the puppets " appear , for example , to walk through doors ( although the control wires make this impossible ) or pick up a coffee cup ( although their fingers are not in fact <unk> ) . " Live @-@ action shots of human hands were inserted whenever scripts called for more <unk> actions to be performed . 
