Halsman, who was born in Latvia in 1906 and died in New York in 1979, was deeply interested in psychology and spent hours engaging with his subjects about their interests. He often asked them to jump, and he noted that, in doing so, their “attention is mostly directed toward the act of jumping and the mask falls so that the real person appears.”
One of Halsman’s most iconic photos, Dalí Atomicus, depicted Spanish surrealist Salvador Dalí playfully floating in mid-air alongside cats, easels, a chair and a stream of water.
Among others—including those of Winston Churchill and Marilyn Monroe—Halsman’s photo of Ali, who died Friday at age 74, remains one of his most surprising images.
Ali—who has been featured on the cover of TIME four times—first appeared on the cover in the issue published March 22, 1963, when his name was still Cassius Clay. He again appeared on the cover on Feb. 27, 1978, featured in a story that concluded, “He is unlikely to go quietly into the past.”
For much more on Muhammad Ali, see TIME’s ALI: The Greatest, a 112-page, fully illustrated commemorative edition. Available at retailers and at AMAZON.COM