The art of making something from nothing has always been at the heart of hip-hop culture. D.J.s in South Bronx parks created a global youth culture with just records and a sound system. And in that analog world, photographers fittingly documented the emerging scene on film. Decades later, those contact sheets are a visual primary text that offer a valuable peek into how artists on both sides of the camera worked.

“I always loved contact sheets because they’re tangible artifacts and you can mark them up,” said Janette Beckman, who made early memorable images of Run-DMC, Slick Rick and other up-and-coming stars. “It really is a record of a photographer’s way of working. You can’t see that in digital. It shows the whole photo shoot and what took place.”

While some rappers today are media moguls, the early years had a potent motivation too: love of the craft. “In the old days, people were doing it because it was their passion,” Ms. Beckman said. “They weren’t doing it to be millionaires. Some of that purity and spirit still exists in the same way.”

Now, in “Contact High: The Visual History of Hip-Hop,” (Clarkson Potter), Vikki Tobak has put together narratives told by the very image makers who helped shape the culture, discovering fascinating stories and lessons on those sheets.