He became interested in photography thanks to his father, who in Livorno ran his own studio, without following a too-provincial and conventional approach. Intended to have a military career, he soon became a photographer for the Army and took part in many war campaigns, creating documentaries on various fronts until 1943.
Having trained in art at the academy, he took retro-style portraits, but his fame is above all related to pictures of Livorno, of its people and its Naval Academy. His most beautiful and artistic photos are those that portray the naval school Amerigo Vespucci: his suggestive glimpses and details heighten the light and shadow. Miniati is able to grasp, as a proper inhabitant from Livorno, that deep bond uniting man to the sea.