Quantum Mechanics postulates that the act of observation affects the behavior of the observed object.The most common example of this feature is the fact the unobserved object(e.g. a photon) behave like a wave in a superposition of states while when observed it starts to behave like a particle with a defined state. Now my question is : It's also correct to say the act of observation rally define the object's proprieties? It's correct to say that different choices made by the experimenter about which observable will be observed leads to different states and properties of the observed object ? I often read something similiar but i want to clear up my confusion about this so i will avoid any misunderstanding.