"Ernest Cole: Lost and Found" is the latest from Haitian director Raoul Peck, who made the Oscar-nominated "I Am Not Your Negro" about U.S. writer James Baldwin.
Playing in a special screening at the Cannes Film Festival earlier this week, it tells the story of Cole who documented the horrors of apartheid in South Africa until he was forced into exile.
Peck told AFP he wanted to reconnect the photographer's story to "the world of today."
It focuses on Cole's difficulties in exile, which resonated with Peck, whose family fled Haiti when he was eight.
It shared the L'Oeil d'Or prize for best documentary with "On the Brink of Dreams," which follows a group of teenage girls in rural southern Egypt over four years, between rehearsals, as they navigate the tough decisions that will determine their adulthood.
The film "is intentionally feminist in every way but I think it was also dictated by what this inspiring group of women was already doing," co-director Nada Riyadh told AFP.
It's "mind-blowing because they're demanding answers about very important things and opening a dialogue with everybody in their community."
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