Beautiful, heartbreaking, ambitious, and spiritually invigorating. “The Salt of the Earth,” a new documentary directed by Wim Wenders and Juliano Ribeiro Salgado, gives social documentary photographer Sebastião Salgado (the co-director’s father) center stage and illuminates his life’s work with a focus on his photography work and travels.

Salgado’s photographs cover diverse subjects, from migrants to workers to the plight of Africans. His photographs seem to share a common theme, however: an attention to visual beauty balanced with a profound compassion towards the different people he befriended and photographed.

The main body of “Salt” consists of Salgado looking at his own pictures projected on a screen and reminiscing about the conditions in which the photographs were taken. This is interspersed with voiceover narration by the two directors, video footage of Salgado’s travel adventures and his restoration project in Brazil.

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In a roundtable interview at which both directors were present, Wenders (“Pina”) examined the process of incorporating the directors’ voices into the film: “For the longest time we thought that there’s only one voice in the film and that’s Sebastião’s and he’s telling all these stories. So the golden rule was that the two of us would totally refrain from interfering. And it took us the longest time to realize that that was the wrong approach and we needed also to appear as narrators and throw the ball to each other and become two voices without interfering with the fact that Sebastião was the overall voice.”

The process, according to Wenders, was long, and the result is that there are multiple authoring presences in “Salt.” Both Wenders and Juliano Salgado narrate the film intermittently, guiding the viewer through brief synopses and commentary of the photographer’s life. The main voice of the film, as Wenders suggests, still belongs to Salgado, nevertheless.

However, from the bits of narration provided by Salgado and Wenders, one expected more scope devoted to Sebastião Salgado’s role as a father or more interactions between him and Wenders (an accomplished photographer himself) since the narration by the two directors hint at this. But this area is only alluded to and plays second fiddle to the main focus of the film, Salgado’s recollections from his photographic projects. These interesting directions that the film could have taken but that it ultimately does not, feels like opportunities lost. And even though “Salt” is undeniably thought-provoking, its success rests more on the choice of filming a subject as fascinating as Sebastião Salgado, a man who has travelled all around the world and seen what most of us never get to see in a lifetime, photographing both the most beautiful and the most devastating sights of the world.

That’s not to say that “Salt” is not worth seeing. Salgado’s story is like a prism that helps us peer into mankind’s recent history, all its tragedies and follies for the past forty years. And despite the sometimes teetering balance between the filmmakers’ narration and Salgado’s personal accounts, the film still manages to pull off what it was most anxious to represent, the remarkable and sometimes harrowing tale of an extraordinary man.

WHAT HAPPENS NEXT: Wim Wenders’s “Everything will be fine,” starring Rachel McAdams, James Franco and Charlotte Gainsbourg comes out shortly.