Some social media stars are big enough to warrant monographs of the kind typically reserved for old masters and big-ticket contemporary artists (one such book is on our Trade Paperback list this week; see Bestsellers).

Humans of New York (St. Martin’s, 2013), based on Brandon Stanton’s blog of street photography and interviews, is a titan of the genre (2.8 million people follow Stanton on Instagram). To date, according to Nielsen BookScan, the book has sold more than 379K units in hardcover, and it’s done particularly well for outlets like MOMA Retail, which, according to book manager Norman Laurila, has sold more than a thousand copies online and in its bricks-and-mortar stores. FSG published a follow-up, the children’s book Little Humans, in 2014; it has sold more than 58K hardcover copies at BookScan-tracked outlets since its October publication. Later this year, St. Martin’s will release Humans of New York: Stories (Oct.), which will follow the format of the original closely, taking an even deeper dive into the personal tales of the book’s subjects.

Tyler Knott Gregson, a poet and wedding photographer, has built a following of 228K on Instagram with his photos of poems typewritten on colored paper. The online enthusiasm for his work prompted Penguin’s Perigee imprint to publish his poetry-photography book Chasers of the Light (2014), to sales of more than 35K units to date, according to BookScan. Perigee will release Gregson’s All the Words Are Yours, a volume of photos of typewritten haiku, in October.

But having a large following on Tumblr or Instagram does not guarantee that an author’s book will be popular. Perigee publisher John Duff says that books like Gregson’s succeed because a consistent tone and “underlying purpose” gird the whole project: “It’s not just posting random photographs. We look at something and say, ‘This is a great blog or Instagram account, but does it have the whole package that you would want to have on a coffee table?’ ”

This also points to the need for publishers to be cautious about which Instagram stars they sign up for books, not just because customer interest might wane but because retailers may move on. “If someone like Urban Outfitters or Anthropology decides that something fits with their mix of merchandise, that’s great, but that changes season to season,” Duff says. “We have to be very careful picking and choosing projects.”

In October, Penguin will release The Sartorialist: X, by street-fashion photographer Scott Schuman, who runs the popular Sartorialist blog and has 536K followers on Instagram. Schuman’s first book, The Sartorialist, sold 39.8K in paper, per Nielsen BookScan. The new book includes professional style shots from London, New York, Milan, and elsewhere, taken with a traditional camera, but also includes six collage spreads of images Schuman snapped with his iPhone. “I think it goes to show that while photographic equipment can be important, sometimes you can still take an amazing photo with just a camera phone and a good eye for the perfect moment,” says Meg Leder, the book’s editor. She adds that the proliferation of smartphones and social media platforms has “really opened up the idea of what an art or photography book can be.”

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