Just a small clarification, you're talking about a different Shah - Mohammad Reza Pahlavi, the guy who was in full control after the 1953 coup, took initial power in 1941 with foreign help (to help out with WW2 due to the strategic location of Iran for oil and supplies to the USSR) from his father, Reza Shah, who took power in 1925 from Ahmad Shah Qajar, who would have been the Shah your grandfather has pictures with.