I found these photographs last week while looking for pictures of my uncle (pictured in the lower photograph on the left, holding a basket of flowers). They were taken when the stone marking my grandfather Stephen Popp's grave was installed at St. Michael's Cemetery in Binghamton, NY. He died 8 Sept 1948.
The priest blessing the stone is likely Rev. Michael Tidick, who was the pastor of St. Michael's Greek Catholic Church and presided at the funeral. Given the weather likely during winter in New York's Southern Tier and that pansies were planted on the grave, I suspect the service took place in the early spring of 1949.