The British Film Institute’s re-release of the rarely seen and now beautifully restored David Lean film The Passionate Friends is only the tip of the iceberg in terms of the celebration of the centenary of the great British filmmaker’s birth. In addition to the rediscovery of Lean’s superb 1948 romantic drama – a kind of companion piece to Brief Encounter – the BFI is re-issuing nine more titles which together constitute the master’s first ten films, starting with the 1942 propaganda/state-of-the-nation drama In Which We Serve and ending with the 1953 working class comedy Hobson’s Choice. Each one of them has been painstakingly restored to their original condition (or near-as-dammit) by the BFI National Archive at considerable expense (a cool £1 million) to the David Lean Foundation, and they arrive on tour in Scotland next month courtesy of the BFI and Glasgow-based classic films (re)distributor Park Circus.

It took the lab-coated boffins at the Archive, located in Berkhamsted just north of London, three years to restore the ten films. Andrea Kalas, the Senior Preservation Manager there says, ‘You start by sourcing the best original material, but with Brief Encounter for example there were no original negatives left. We looked everywhere, but they’re just gone. So what we had to work from was a what I call a vintage fine grade negative, which is a copy of the original that was made at the time the film was completed. However, it was really, really damaged.

‘So,’ Kalas continues, ‘with Brief Encounter we didn’t have good enough quality original elements to do the standard photo-chemical restoration, which involves working directly from whatever negative you have. What we had to do was a full digital restoration, which means scanning into a computer the original elements, cleaning them up pixel by pixel, and then recording them back out to film. Then, in contrast to that hi-tech method, one of the team suggested cleaning up In Which We Serve with cotton buds. I thought, “That’s going to be a lot of hard work”.’

The results are glorious. Gone are the scratches and crackles, colour fading and contrast variations that marred the experience of watching these wonderful films. Now Guy Green’s Oscar-winning chiaroscuro photography on Great Expectations can be fully appreciated in its unblemished glory. Now we can hear each delicately delivered line of dialogue (and every awkward pause) between Celia Johnson and Trevor Howard in Brief Encounter. And now Scottish audiences in particular can enjoy Lean’s meticulous recreation of Victorian Glasgow for the period drama, Madeleine.

‘We were driven in this restoration project by Lean himself,’ says Kalas. ‘He was an amazing technician and very perfectionistic. He was absolutely determined to get the perfect contrast, the play between light and dark that’s so remarkable in his films, and likewise, we were determined to overcome the huge challenges this project presented.’

Talk about passionate encounters.

The Passionate Friends is at Filmhouse, Edinburgh, Mon 21-Tue 24 Jul.