For almost a century, physicists have been discussing the influence of the ob-server on the observed field, in particular that of light, and have come up against theHeisenberg uncertainty principal when they push the corpuscular theory to the exami-nation of the evolution of a single photon. Art market observers, on the other hand, tend to favor wave theory, looking fortrends and establishing their variables on the basis of price indices and quotations thatowe very little to chance.More than waves propagated on the technological networks, and quite foreignto the fashionable subjects, the second Biennial of Photography of Senigallia has beenorganized during the epidemic around a model of successive individual initiatives andwithout directive determinism. Hence the title of Photographic Archipelago for this re-solutely and joyfully disparate program that invite the public to discover unexpectedphotographs and to meet other interested people in the middle of a city where eachinhabitant, shopkeeper, hotelier, fisherman, worker, farmer, has a personal opinion aboutphotography.The singular sun, reflected on the Adriatic Sea in the morning, illuminates theclear streets of Senigallia. The installation in 1939 of an art theorist and promoter of pho-tography, Giuseppe Cavalli, but above all the determination of a typographer with thedestiny of an artist, Mario Giacomelli, were the favorable circumstances that impelledan entire city to become aware of the importance of photography, to become città della