02/27/2013 at 03:00 PM EST
Capturing the Beatles' casual, off-duty moments never felt like work for Henry Grossman.
"We were friends," says the former photographer for both Life and PEOPLE, now 76. "I almost didn't know them as performers."
His new 500-page photo book, Places I Remember, features nearly 1,000 never-before-seen photos taken at the height of the band's fame, between 1964 and 1968. Why did it take him so long to share?
"I had pictures I didn't know had never been seen," says Grossman.