For the past couple of years I've been getting my accreditation and nipping off to see a few films at the London Film Festival. It always felt a bit special — seeing films before they were officially distributed — or films that might not get UK screenings — and a day spent watching two or three films back-to-back could leave me inspired, my head spinning with ideas. This year I can go and see my own film, Black Sun, and I probably will, as I've been asked to attend the screenings to introduce the film and stay for a Q & A session afterwards. The film has already been shown at Toronto Film Festival, and despite my trepidation that no-one would turn up, it sold out and received encouraging reviews. Also, I got to see Toronto: a lovely place full of lovely people.

So to London, my home (where I suppose I'm slightly more prepared than in Toronto), and the sort of things that will occupy me for the next few days. Apart from the screenings themselves, this will include meeting the press and other film-makers who will be doing the same thing. And hoping that the cinema will be full, that a distributor will be there and will enjoy the film as much as some of our Canadian reviewers. Distributors are the vital link between your festival tape and securing cinema distribution, but as far as which films are going to get picked up at any particular festival — well, it's anyone's guess. There has been a lot of talk in the film press recently about feature documentaries riding a wave — thanks to the success of Fahrenheit 9/11, Supersize Me, The Fog of War etc — and as my film falls somewhere into that category, perhaps we are in the right place at the right time.

I started to make Black Sun in the summer of 1999. I had spent the previous ten or so years working as a media composer, writing for commercials and short films, and looking around for something more substantial to compose to. But the kind of films I was interested in seemed to be made largely by people who used the same composers over and over again, or by people who were now dead, so I didn't really see a career looming.

Having been inspired by punk rock as a teenager, growing up in London in the mid-late 70's, I don't think I have ever lost the "can-do" attitude, the inclination to reject the idea that one can be excluded from any enterprise simply because one doesn't have the requisite connections or qualifications. So I decided to make my own film, and to do every part of the process myself (shooting, editing, composing the score, producing and directing) just to see if it could be done. And because I felt I would learn more about the process if I took on responsibility for every part of it myself.

I looked for a subject. I had in mind a kind of poetic documentary, following in the tradition of films like Dziga Vertov's The Man with a Movie Camera, Errol Morris's Thin Blue Line, Chris Marker's Sans Soleil and Godfrey Reggio's Koyaanisqatsi. My local video shop used to have a shelf marked "unclassifiable" (and may still do — with two small children it's been a while since I was there) and all these films were on it, and I guess I liked that. They were just a little bit different, but still had great resonance.

I remembered a book I had read back in the 80's, a biography written by a French artist who had been attacked and blinded while living in New York. Something about the story had stuck, and I managed to track down the author, Hugues de Montalembert, who was living in Denmark. I called him, and pitched the idea for an "experimental" documentary; we agreed to meet in Paris two weeks later.

When we met, I played Hugues some pieces I had been working on, using spoken word integrated into an orchestral score, which he liked (fortunately we both like similar music) and he agreed to do some interviews, which we did over the following couple of days.

I returned home and over the next few years, when I had time, went on trips to pick up footage. Armed with my 1970's 16mm Canon Scoopic film camera that I had bought over the internet (and which I taught myself to use on the fly), I amassed hours of film, which I started to edit into shape. I cut up the interviews, editing the content to create a narrative, and then re-gridded the words to create a new spoken word track with a poetic metre. I started composing to this track, and simultaneously worked with Apple's Final Cut programme to edit images against this soundtrack. By February this year I had a rough cut, which a friend recommended to John Battsek — the British producer of the Oscar-winning documentary One Day in September — who was enthusiastic about the project and agreed to help take the film onward. As did my friend the director Alfonso Cuarón, who helped me by going through the rough cut and offering his comments, which was very useful after my years of solitary work.

And so: you reach a day when you say "finished", fill in the festival application forms and send off your DVD. And wait.

And if you're lucky some weeks later you get a lovely e-mail or a telephone call that tells you you're selected, and then the film starts to have a life of its own. And slowly dates in your diary loom closer, then arrive, and pass.

My entry for tomorrow reads: "6.15pm UK premiere for Black Sun, LFF. NFT2. Q&A."

I hope somebody turns up.

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