It was like watching a matinee with the theater doors open. There was nothing close to a true black in the entire movie. Only a middle grey at best, making it difficult for me to watch. Was that intentional, maybe to make it look ethereal? It sure didn't work for me.
It was very much intentional. The great DP of Selma, Bradford YOung, said that both him and Ava Duvernay were impressed and impacted by the photography of Paul Fusco, who shot the people viewing the body of RFK as it travelled the eastern seaboard after his assasination. Young said they wanted to use this color palette, imitating a Kodachrome film look, because these photos were so grounded and impactful to them.