Jay Z

How did you decide who to invite?
A woman named Jeanne Greenberg Rohatyn did the invites. She's an art dealer in New York and has an association with Jay Z. But we didn't want it to be an elitist art world thing. There were many artists who were interested in seeing the event and who came. But we wanted to make sure people from all walks of life and social strata could come, including people who were huge Jay Z fans. People didn't know what it was, exactly. They knew it had something to do with Jay Z but they didn't know what it was or if he was even going to be there. There was a nice quality of surprise and excitement.

How did you deal with the crowd? Could people just hang out all day?
We had to control the flow of people, partly because the film office and the police were very concerned because if it spread through social media it could become something where they couldn't control the amount of people. We had 250 people at a time and we had about nine or ten groups of people. Jay did the song maybe four or five times for each group. And then we had to recycle them. And it all went off quite smoothly. Had it gone viral and gotten out of control, it could have been another exciting thing to film. But it's probably better that it didn't.

"I was continually surprised. And that's what's so joyful about watching it, too. It's kind of an endlessly inventing, surprising thing. It's a tsunami of joy."

What were you most surprised by?
I was continually surprised. And that's what's so joyful about watching it, too. It's kind of an endlessly inventing, surprising thing. It's a tsunami of joy. Everyone is having such a good time, Jay is having such a good time. Some people came and sat and absorbed the experience. Other people felt the need to perform or collaborate or come up with some sort of gag. There's no one encounter that is similar to another. It's a whole range of surprises. We had 30 hours of film, because we had 8 cameras going.

Are there any plans to do anything else with that footage?
We had some deleted scenes but I think we had a chance to artfully manage it. There was some talk of cutting it even more. The only person that Jay performed the song for from beginning to end, since most people sat for 30 to 60 seconds, was Marina Abramovic. We should probably put that version together.

How quickly did you have to turn this around?
At the end of the day, we had a bit of time. Everybody worked 14 hours a day from the moment we finished shooting until yesterday. But when Jay made the arrangement for it to premiere on HBO we knew what our delivery date was we had a little bit more breathing room. We had a mixer who has been nominated for 16 Oscars, who did "Schindler's List," which was great because it was a tricky mix. It's all live vocals. There's no lip-synching. The whole point was having a live document. So it was a challenge. We had four or five editors on it at any given time, trying to make sure we were capitalizing on the giant tidal wave of footage.

Were you worried about losing that sense of spontaneity?
To be honest, I wasn't worried about it. We could see how it was coming together in the spirit and tone we intended. It was so live and real. So the challenge was really how can we create a nice flow and structure to it and not leave out any of these terrific spontaneous encounters and these little sweet moments. And that's just artful editing. The filmmaking is very transparent. We didn't light anything. We chose a gallery that allowed for this great sunlight. We tried to make the filmmaking have as light of an impact on what was happening as possible.

What's next?
I've got three projects, one of them I wrote, another one's a black comedy, another one is a drama. I do want to make another film. That's my main goal.

Have you given up on trying to make a big studio movie?
I've made my attempts at making these large-scale studio pictures and it's not gone well. And perhaps what it's telling me is that I'm better suited to more medium-sized types of projects. I think that's a happier place for me to be.

Jay Z and Mark Romanek's "Picasso Baby" premieres on Friday night at 11, right after Bill Maher. Check out a preview below along with a montage of Romanek's music videos.