We may be a couple of months late to this party, but it’s still a great find.

The Louis Armstrong House Museum recently acquired footage of Satchmo singing and playing on a 1959 recording session. It is the only known film of Armstrong in a recording studio.

The 33-minute film flew under the radar after being commissioned by record producer Sid Frey, who decided not to make use of it. Frey kept the footage a secret, but it was eventually discovered by his daughter and ended up in the hands of the New York-based museum.

The film shows Armstrong recording his 1959 album Satchmo Plays King Oliver–a tribute to his mentor Joe “King” Oliver–in Los Angeles. The session also featured clarinetist Peanuts Hucko, trombonist Trummy Young, pianist Billie Kyle, bassist Mort Herbert and drummer Danny Barcelona.

Sometimes it seems like the Louis Armstrong’s legacy will never run out of surprises. Crystal clear recordings of two 1920s-era Armstrong tracks surfaced back in April, and the Smithsonian released a video of New Orleans’ own Wynton Marsalis playing Satchmo’s trumpet last month.