Ranbir Kapoor, who is all set for his second release 'Bachna Ae Haseeno', says constant comparisons with his father Rishi Kapoor are inevitable, but feels that he won't be able to match up to his father's on-screen charisma.'I know the audience seeks another Rishi Kapoor in me. But I can never be like him. He is such a spontaneous actor,' Ranbir told...