It's been two years since I did this work but I believe we were invited to take part in the project because of the success of the Con Passionate fantasy sequences. The initial brief was for us to provide a title sequence and incidental matte paintings for the series. Since it was set in 1927, the production wanted to film Blaenavon and then use matte paintings to mask out any modern buildings or elements that would otherwise take you out of the story. The title sequence was equally ambitious and reminded me of the Cold War titles where the camera slowly moves across a model landscape that dissolved from landmark to landmark through time. Their idea was to film a helicopter shot travelling up the valley and slowly have it transform from the modern day back to 1927 by the time it reached the pit head and the location of the miner's houses. We were really looking forward to doing all of that, tracking the shots, building the necessary 3D augmentations and creating the fantasy that the people really were in that era. Sadly, the budget got cut and cut and soon we realised that none of our effects work was going to happen. Then, BBC publicity contacted us and said that they were planning to film a cinema advert for the series and that it would require a lot of visual effects to save filming the mine shaft and lift for real. The 40 second advert would have the live action filmed on greenscreen and we'd need to build all the surrounding rock and brick shaft as the families slowly changed from modern dress into period costume.

Filming took place in Enfys where we'd shot Con Passionate but, for some reason I can't remember, I wasn't able to be there very long. We received the edit fairly quickly and I spent a lot of time getting the keying right. Unfortunately, because the interior of the lift cart was meant to be dark, it was lit dark. However, the greenscreen remained at its usual bright setting and so every shot that featured the grille on the sides of the cart in the background had the bright green of the cyc bleeding into the dark foreground. This because, when out of focus or semi transparent, bright colours overwhelm dark colours. The upshot was that nearly every shot had the grille eaten away by the green and it became very blobby. Luckly, the darkness of the film worked to our advantage and we were able to disguise with a lot of recolouring but it's a lesson I've learned to this day - balance the brightness on a greenscreen and recolour in post.

Like the Pobol Y Cwm titles, which we'd only just finished or were just finishing (perhaps that's why I wasn't at the shoot), I decided to composite in Fusion for flexibility, although the keying was done with Keylight in After Effects. This was another HD project and I didn't want to take any chances. I only wish we could have bought Fusion after that but the projects have never had the budget to pay for it and it would have been too complex a program anyway. After Effects is best for quickly dealing with a volume of shots.

As before, Llyr handed the CG work with Romano and I did the compositing. For all the interior shots, I keyed everything and tracked the backgrounds in 2D before adding in a matte painting of the moving background that had been rendered out for me without motion blur at 10 seconds long so that I could drop it in anywhere. The rest of the fully CG shots were all rendered in passes and then composited with the additional depth passes to add realistic depth of field and len bokeh. We had been fortunate to have a recce to the Big Pit at Blaenavon and have a special tour of the site to take photos. We even got to look all the way up the lift shaft, something that people are not normally allowed to do for safety reasons, and that proved a big help when we were building and lighting the CG shaft - it had to look as damp and uneven as the real one.

Again, we were right down to the wire for the advert but it proved a great success and looked great (I'm told) on the cinema screen. Sadly, I didn't get a chance to see it on the big screen because I was doing something else at the time. In addition to this advert, we also rendered out about a minute's worth of the lift travelling down the shaft so that the BBC could use it as part of their circular BBC1 logo/ident. At least I got a chance to see that and it looked great on screen!