Famous for his comedic roles in the Infernal Affairs trilogy and Initial D, actor Chapman To Man-chak has been extending his adventures behind the screen as a producer. After producing Pang Ho-cheung's Isabella and Trivial Matters, To's latest venture is young female director Heiward Mak Hei-yan's Ex, which closes this year's Hong Kong International Film Festival. Featuring singer-actress Gillian Chung Yan-tung in her first movie role since her photo scandal, Ex is the second feature from Mak, whose first short film Lovers' Lover won the Young Film Makers Award at the International Film Festival, Hannover, in 2007. You have overseen three movies since Isabella. How do you feel about being a producer? It's really agonising. As an actor, you are mostly emotional; you don't need to be pragmatic. In contrast, being a producer is a rational job. To ensure a smooth production, you have to make some compromises, and sometimes you have to force the director to compromise as well. The hardest part of being a producer is that you have to forget about your image, put your ego aside and be able to keep a lot of secrets. Otherwise there is no way you can do this job well. In fact, the job of producer is not common in the Hong Kong film industry. Most of the time, the director will take on the role of producer because, in the old days, many producers only cared about the schedule and the budget. They just cut off the power when the time was up and told you the money had run out. That's why when directors become famous, they often drop the producer position to control the filming schedule themselves. In fact, this is not healthy. When I was hosting a radio show with [actress] Sandra Ng Kwan-yue, I often visited [her husband] Peter Chan Ho-sun's offices after work. I learned a lot about producing movies from him, which inspired me to be a producer. I think Hong Kong movies need proper producers, just like in Hollywood. But unlike Hollywood, we are making movies on shoestring budgets. So it's even more important to have someone to be the producer - to serve as the middleman between the film company and the director, and to maximise the profit and minimise the loss. So do you enjoy doing such a tough job? I enjoy it very much. It has made me a more mature actor. I know it's not easy to complete a movie. Now I treasure my job more and have a greater understanding of other roles in a production. In the past, I was concerned only about my performance and didn't care about the rest. Now, I will consider other positions and try to make everyone happy during filming. Was the latest production experience different from previous ones? It's very different each time. Directors can be very intimidating creatures. They seem to be very open to opinions, but deep down they are highly subjective. Being a director is all about pride and prejudice. This is the nature of a director. How to work with them is a big challenge. It's very satisfying when you successfully handle such a challenge and oversee a film from start to completion. What drove you to partner with Heiward Mak this time? She refuses to grow up. I appreciate that because I don't need a director who craves maturity. Many people have asked me why I'm not a director myself; the reason is that I don't know how to put together the different frames of images in a movie, and I can't remember the feeling of being young any more. It's scary that I've lost this feeling now I've turned 40. So I want to find someone who still has that feeling - it's something money can't buy. I want to offer some new directors the opportunity to develop their skills and talent. Do you think it's risky to cast Gillian Chung as the lead? My boss asked me the same question. Objectively, maybe I shouldn't take this risk. I know that Gillian has stopped making movies for the past couple of years, since the photos were leaked [in 2008, sexually explicit photos of Chung and a number of other starlets were released online]. But it's ridiculous if she loses her chance of making movies for this reason. It's fair to kick her out if she is not professional enough, but she has never made any big mistakes as a professional actress. The director proposed her for the role, and, after reading the script, I agreed she was a suitable person. I thought, why not? I'm very satisfied with her performance in the movie. She was very well prepared for her part - you can see it from her acting. You've recently quit smoking. What prompted you to stop? I felt pain in my lungs one day last year and quit. I'm getting old and I think I need to pay more attention to my health. It's also good practice for me to learn self-control. When I watched Love in a Puff [Pang's new film] last night, the feeling was really funny. It was so tough for the actors to keep smoking in the movie. Ex premieres at the Hong Kong Cultural Centre on April 6.