Jimmy Nelson’s seminal work “Before They Pass Away” broke many records for a hardcover photography book and rightly so. His work ethic and attention to detail set high standards for all photographers, and as a body of work documenting the remaining tribes in the world it is in a league of its own.

Yet he did take some criticism. Some of the staged shots were a departure from reality in that the tribes were playing to Jimmy’s camera and dressing up for the occasion, swapping their usual clothes for tribal outfits that 99 percent of the time remained in the bottom drawer. Some claimed his work was misleading.

I have considerable sympathy for Jimmy on this issue. In photography, the presumption of veracity lends authority, but he is an artist, not a National Geographic photographer. He never claimed these images were snapshot aesthetics of day-to-day life. He is a brilliant artist and, to me, that is that.

I have mostly avoided tribal work, partly because of this debate and partly because Jimmy did it so well that it was a category-killer body of work. However, I do feel that South Sudan is different because there are Dinka cattle camps there that are both raw and timeless. There is no need for a photographer to manage the aesthetics of daily life, because daily life is visually powerful as it is. There are many guns distributed among the cattle camps in South Sudan, and I can assure you they do not come out solely for the pictorial benefit of visiting photographers.

This late afternoon near Yirol, in the heart of a troubled young country, will live forever in my memory. In many ways, it changed my life.