Short-film festival Tropfest NY will unspool at the World Financial Center Plaza on Sept. 26.This year marks Tropfest’s first as an independent effort. It had been associated with the Tribeca Film Festival. Event will screen 16 shorts and hand out a $20,000 cash prize and a trip to Australia to the top filmmaker. An aud nod will be presented to the crowd favorite. Each year filmmakers are required to incorporate one item into their shorts decided by the organization; this year it is a sunflower. Shorts must be no longer than seven minutes. Submissions are being accepted until Sept. 5.