g'day Michel

great question

without the photograher there would be no image and no record of Picasso's work, so if the cetaur was not recorded is it art?

the resulting photograpgh is a piece of visual art, would it have been as good without the Picasso drawing? it would still exist but thr centaur drawing wouldn't

so, i must consider it a photograph by Gjon Mili with some input by Picasso