Imtiaz Ali is making Rockstar on a tight budget as producer Ashtavinayak is facing a money crunch.

The director is trying to cut costs in every possible way. He recently took the shots of the Bryan Adams' concert in Mumbai to get a live audience and save expenditure.

A source says that though the director had several producers queue up for his project starring Ranbir Kapoor, Imtiaz chose to stick to the producer who gave him his biggest hit Jab We Met instead of getting lured by other production houses.