Keanu Reeves' new filming documentary 'Side By Side' was a personal and intimate process.

Keanu Reeves thinks making 'Side By Side' was a deeply personal experience.

The 'Matrix' actor - who made his producing debut alongside Chris Kenneally - says his new documentary, which tackles the debate between traditional and digital processes of fimmaking, was an intimate journey for him.

Keanu told "'Side by Side' is an expedition for me and for Chris Kenneally. When we were in Technicolor in New York, I said 'Wow, this is changing lets go do this. Chris do you want to go do this? It's really personal.'

"Chris said, 'It may be personal, but we have to make this for everybody, this is for the specialists, for the general audience. It's about movies, movie making, it's a behind the scenes.'

"So, for me, the people that we approached, it was personal."

The 47-year-old actor approached legendary directors James Cameron, David Fincher, George Lucas, Christopher Nolan, Martin Scorsese, David Lynch, Stephen Soderbergh and Andy and Lana Wachowski to share their experiences of the big screen, and still can't believe they all agreed to participate.

Keanu enthused: "All I can say is that I am really grateful that they took the time to meet with me. And they have a wonderful passion, knowledge and experience in storytelling, in movie making.

"It just kind of opened up. To be able to speak to people who have such knowledge and passion. I don't know why they said yes, but I'm really happy they did."