If you enter our AV test room, you will find a vast selection of 4K Blu-rays lining the shelves. That includes many new discs, but there is also a healthy collection of older movies that have had a 4K restoration. Master and Commander: The Far Side of the World, for instance, has quickly become a go-to for testing both sound and picture quality.
But how do these 4K restorations actually happen? To answer that question, I headed to Silver Salt Studios, which has restored countless titles. That ranges from Hammer Horror films, including The Curse of Frankenstein, to the 1995 TV adaptation of Pride and Prejudice.
Preparing the film
The journey starts with me making my way to the studio's headquarters, which are hidden along a side street in London, nestled between a row of offices. This is where the restoration magic happens, and I took a tour of the studio to see how a reel of old film becomes a gloriously bright 4K movie.
Once there, I'm greeted by Marie, who works with the original negative of the film being restored. These are often found in a less-than-desirable condition, as is the case with the one she's currently working on.
She gets it onto a specialised bench for inspection (as in the above image), where she carefully examines the reel frame by frame to find the damage.
There are a whole host of ways the film can be damaged. Marie shows me just a few, using the 1954 release The Men of Sherwood Forest as an example. There was a custom stamp at the top of one frame. Some were missing the sprockets on the edge, and various scratches and rips appeared across the film. Not to mention the reels have been sat in an archive for decades, so they can be further damaged by mould.
To my untrained eye, it seems like a lost cause. But Marie and the team managed to restore the film so you would not even think that it was found in such a sorry state.
After the damage is noted, Marie puts the reel through a special cleaning machine which winds the film around a series of little buffers to remove the surface dirt. If the film is particularly damaged by mould, she will hand-clean the reel to destroy the spores as best she can.
“I usually let the film build up and then have a big washing session”, Marie says, pointing to a few film reels lying on the side that are yet to be cleaned.
A Scanner Darkly
Next, I meet Silver Salt MD Mark, who is clearly very proud of the two scanning machines next to us, which he shows off with a smile.
One includes a wetgate, which is a particularly impressive piece of kit. If there’s a scratch across the film’s emulsion, it can fill the hole with fluid to remove the imperfections. “It’s great in theory, but getting it to work every time is another story,” says Mark.
The films are scanned in 6K, then downscaled to 4K. That turns the negatives into a raw DPX file, a digital format commonly used to transfer film images.
The artists at work
We move to a dimly lit office, with every screen displaying a frame of film that is at least 40 years old. Head of Restoration, Anthony, demonstrates how the scanned film gets divided among different members of the team, who remove more imperfections.
There are countless different computer software programs involved. He shows us one that highlights flecks of dirt in the image, and another that highlights tiny scratches. But the entire process calls for the human eye to painstakingly remove them piece by piece.
After all, the software cannot always tell the difference between the texture of a white sequined dress and snow, and might pick out the edge of a trouser leg as a stray bit of dust.
“Despite what people may think, we spend most of our time putting back in rather than removing dirt”, he comments.
Processing damage is one of the most difficult things to remove, Anthony tells me. He shows one film that previously had a yellow staining for about 15 frames but, after the team got their hands on it, is now imperceptible.
As the rest of the team gather around the screen to admire the work, they joke, “Whenever you have worked on something, you’re always looking at the frame like this,” before leaning in closer to the screen with a grin. To me, I would not have even known it was there.
They must also stabilise the image, then carefully watch each frame in quarters to make sure nothing has been missed. Once this part of the process is complete, they are left with an image that is incredibly detailed and clean.
Adding some colour
The final part of the process is colour grading, handled by Ray. He’s worked on all the Hammer Horror films handled by Silver Salt so far, and that’s just to name a few. He tells me he is retiring this year so his current project, a 4K restoration of the 1958 Dracula, is his “swansong”.
“I think people are really going to like it,” he smiles.
Over time, colours often fade in the original film, so it’s Ray’s job to restore films to their full potential. We get a glimpse of Dracula, which was originally made in Technicolour. The raw footage is somewhat muted and grey, and it doesn’t immediately draw the eye.
But Ray gives the footage a beautifully rich look, breathing new life into each frame. Part of his process is considering what the sets would have looked like at the time. In Dracula, for instance, he brings out the opulent reds in the velvet curtains and the crisp detail of a leafy bush that had fallen victim to black crush.
After playing around with different colours and bringing out the contrast, highlights and shadow, the grading is complete.
The final result feels like magic. What came into the studio as a worn film reel, left forgotten for decades, is now set to delight a new generation of audiences with its beautifully restored colours and crisp detail.
The newly restored Dracula is coming to cinemas and 4K Blu-ray in October. After getting a glimpse into the work that goes on behind the scenes, I'm excited to see the final result on the big screen.
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