Matthew, Alan, Nick Enjoy ‘Diminished Capacity’

Sarah Jessica Parker is out-of-town for hubby Matthew Broderick’s Gen Art Film Festival premiere of Diminished Capacity held at NYC’s Ziegfeld Theatre.

While the SATC icon is away, her man has been keeping busy filming 30 Rock. Alec Baldwin entertains by doing impressions of Marlon Brando — and him. (Ha!)

Working with Alan Alda in this comedy about a man suffering from memory loss was irresistible to Matthew because he’s a big fan of the M.A.S.H. star. “That was the big draw,” the sweet, petite father of one says.

What advice would he give wannabe actors?

“I’ve had a lot of disappointments,” he says. “Don’t give up too fast. Hopefully it will come through.”

In this film, Matthew and Alan head to a memorabilia expo. What does Alan collect?

“I have a nice collection of dustballs under the couch,” he tells me. “That’s about it.”

After Julianna Margulies (and her supercute hubby), Thora Birch and Real Housewives of New York star Ramona Singer slide through, Nick Cannon tells me about his sneaker fetish.

“When I was younger, I wasn’t able to have the coolest sneakers, so when I got old enough to be able to buy them myself, I went overboard.”

Afterwards, the stars party at The Park. Woo-hoo!