Sinha, who traces his roots to Banaras, said that RaOne was a challenge for him because of this.
"I never read comics as a child. Nor did I get to watch superhero films then....While making the film, I was influenced by the things which I had seen in the superhero movies (later)," the director said during an interaction at NFDC's Film Bazaar, on the sidelines of IFFI 2012 here.
"All the superhero films have pretty much same formula... There are some elements which come automatically," he said, adding that therefore "there is a fear -- when movie comes out it should not look like a copy."
To make a superhero film with a star like Shahrukh Khan furthered narrowed the scope for creative license, because audiences identify King Khan with a certain image, he said.
"You can't make a 'Dark Knight' with Shahrukh. It has to be either Spiderman or Batman."
