I own a SX70 camera with the ultrasonic autofocus and a dedicated electronic flash. It was used in the tropics for 3 years and made 100s of pictures, despite blistering heat. I think its days are over, as the battery in the film pack is a strange flat aluminium foil package, which is unique to Polaroid. I will probably pull it apart and canabalise the lens or see if anything can be done with the single lens reflex system. Maybe it's possible to connect the internal battery contacts to a suitable external battery, with a bit of modification/ butchering...