Chris Dale Reveals the Secrets Behind the Thunderbirds 60th Anniversary Blu-ray

The Thunderbirds 60th Anniversary Collectors Edition Blu-ray is very nearly go! This much-awaited release of Gerry and Sylvia Anderson's beloved television series has proved a gargantuan undertaking in putting together the definitive home media release of Thunderbirds. Originally planned for release in time for Christmas 2025, the release has had to be pushed back for early February owing to the intense amount of work demanded of this set to make sure that Thunderbirds has never looked or sounded as fantastic as it does here.

Now that the Blu-ray release is finally preparing for blast off, producer/writer/director Chris Dale, who has been instrumental in managing the Blu-ray's production, reveals many of the secrets involved in this set. From painstaking steps involve in the restoration process of the classic series to producing an avalanche of bonus material, Chris is here to reveal all!

Fred McNamara: First of all, could you give us some idea of what your involvement with this project has been?

Chris Dale: I’ve been involved with this set in every stage of its development; from being part of the team that initially reviewed the episodes noting issues that we wanted to correct for this release, to helping to formulate the overall extras package and writing/editing/directing/producing various new extras, helping proof-read various paper materials (packaging, booklet, etc) and finally to reviewing check discs prior to the final discs being pressed and packaged. It’s been a long project, but the sets will be arriving with customers early next month!

Fred McNamara: The Thunderbirds Blu-ray was originally scheduled to arrive with fans by Christmas last year, but has now been pushed back to early February. Can you explain briefly the issues you've found that have justified the push-back?

Chris Dale: Almost nothing really has cropped up that wasn’t already known about, but it’s fair to say that we underestimated the amount of work needed to produce the set we wanted!

As most people should know by now, the versions of Thunderbirds that we’re including on this set are masters that were prepared about twelve years ago by ITV. They’re the same versions currently on ITVX and the ITV Retro YouTube channel (and which have been broadcast on Talking Pictures TV in the UK), which have also had German, Japanese and American Blu-ray releases, with 3 episodes also appearing on Network’s 2014 Supermarionation boxset. Clips from them were also used in the 2014 documentary Filmed in Supermarionation and the three 2015 Thunderbirds anniversary episodes, and most recently they were used in Anderson Entertainment’s 2025 Blu-ray release of the Thunderbirds Super Space Theatre movies.

So they’ve been around for a while, but have never before had a UK Blu-ray release in full. While they look lovely overall, there are some points where decisions were made during their production that compromised certain parts of the image in certain scenes; zooming in to crop off print damage on the edge of the frames, adjustments to cover generation drops during fades, etc. We were aware of this going in and to ensure we could fix these we needed to ensure we had access to the LTOs (essentially HD backup copies of the original 35mm film scans) used in their production in order to correct as many of these as possible.

Unfortunately, there was one other additional problem we weren’t expecting…

Fred McNamara: Among the issues found in these checks has been the need for a full pitch-shift correction to ensure audible authenticity of dialogue, sound effects, soundtrack and more. Can you explain what this process involves, and why this may have been incorrect in previous releases?

Chris Dale: Yes, the pitch ‘issue’ has been the main reason for the set’s delay, but it’s pretty simple to explain and I’d like to do that because it has caused some confusion. Thunderbirds was delivered to us with the video running at 25 frames per second (as opposed to the 24 frames per second it was filmed at and should be presented in), meaning that every episode runs slightly faster than it should. Naturally, the soundtrack too was running faster than it should, with the pitch elevated slightly above the norm, so the voices sounded just a little higher than they were originally recorded.

So for this release, since we’re presenting the series in 24fps as it should be seen, we’ve also corrected the pitch back to where it should be.

And… that’s it. Nothing more sinister or extraordinary than that. It’s a fairly standard thing to do with shows and films that have been released in multiple regions.

What’s taken the time though is that we’re also including the 5.1 sound mix that was created back in 2000 for the DVD era. I know some older fans will sneer at that soundtrack’s inclusion, but we recognise that there is a generation of Thunderbirds fans who discovered the series in the early 2000s for whom it simply sounds wrong without those extra sounds – and since those soundtracks were on the files ITV delivered, why not include them? Options are always good.

But then each individual track on the 5.1 mix also had to be corrected in the same way, since they’re also running to 25fps visuals on the ITV files. That means that for all 32 episodes of the original series, you have multiple individual sound files all needing attention, and the work mounts up very quickly. So if there’s a primary reason why getting this set out the door has taken longer than anticipated, it’s definitely down to the work needed on the 5.1 soundtrack.

What’s interesting regarding the difference in pitch between 24fps and 25fps is that not everybody notices the difference. If you look at the ITV Retro YouTube channel, where they’ve been uploading Thunderbirds in 25fps, and read the comments… you’ll be looking for a very long time trying to spot anyone commenting on the incorrect pitch. Most people are just enjoying the show. (How dare they!) The average member of the public cannot tell the difference between how the show sounds at 25fps and how it should sound at 24fps, and while fans are more likely to have a greater understanding of these things and thus more likely to pick up on the difference, they don’t always.

Fred McNamara: Can you summarise just how much effort, resources, and manpower has gone into this entire restoration process?

Chris Dale: In a word; lots! In the beginning, the entire series was divided up between a group of Anderson Entertainment team members (people who have ate, slept, and breathed Thunderbirds for decades, and so know this material well) with each of us getting (on average) six episodes each to review, looking for the various picture flaws or problems in these particular masters (plenty of which we already knew about to begin with). We also reviewed the original audio track and the 5.1 audio track for any problems there that could be corrected.

And then… we all swapped episodes and started the process over again! This way we could be sure of giving each episode the best possible chance of having as many of its problems fixed as we could.

Once each episode had been given its four viewings, the shared spreadsheet full of our notes and observations was passed to Stephen Thwaites, our editor who has worked tirelessly on making and inserting the visual corrections (and who also edited together the new HD versions of the Thunderbirds Space Space Theatre movies). We also had help from the folks at Silver Salt Restoration at this stage, to make sure that any shots where we’d gone back to the LTOs matched the grading of the shots before and after. Meanwhile, Benji Clifford was hard at work correcting the audio problems and handling the pitch correction, and gradually each episode began to come together – again!

Once that was all done it was time for the next phase; more reviewing of the finished episodes, and then more reviewing of those reviews via check discs – both internally by myself and set producer Joe Spray, and at the authoring house! So each episode has had a lot of eyes on it at every stage of the process, and nothing went to the final manufacturing stage until we were absolutely sure there was nothing more to address.

It was very important to everyone who worked on this set to get it right; firstly because that’s what customers deserve, and secondly because we all love the show and want to present it as best we can. True, we could have saved ourselves a lot of sleepless nights if we’d just slapped these episodes on Blu-ray at the 25fps they were delivered to us rather than the correct 24fps, left the audio incorrectly pitched, made no attempt made to fix the existing visual errors… and probably a sizable chunk of the people who purchased the set would never have known anything was wrong. That has been done before; the 3 Thunderbirds episodes included on Network’s 2014 Supermarionation set were from these masters and were presented at 25fps (as were all the other episodes on that set), with the picture problems not dealt with, and the only audio track being the 2000s era 5.1 soundtrack converted to stereo at the incorrect pitch… and the world somehow kept right on turning! But that would have been wrong to do here. This team was tasked with presenting the best possible release of these particular transfers, and that is what we have all done with diligence and care to the best of our ability.

There’s also plenty of people to mention who worked on the various new special features for this set, including Andrew Clements, Jack Knoll and Marc Silk who put together a lovely feature looking at post-Thunderbirds Thunderbirds projects; puppeteers Justin and Lindsay Lee who filmed the new mini-episode (written by myself and starring Jon Culshaw and Genevieve Gaunt) Fabblebox,; Ben Page, who compiled a new commentary from archive interviews with original cast and crew, plus those who participated in our new commentaries – including Genevieve again, Wayne Forester, Sophie Aldred, Nicola Bryant, Richard James, Jamie Anderson, Dominic Colenso, Lex Shrapnel, Sophia Myles and Sophia’s dog Phoebe! I also want to mention designers Marcus Stamp, Callum Shutt, and Mike Jones, who between them created wonderful artwork and layouts for the boxset and its accompanying booklet - bolstered by the addition of some cutaway images from Graham Bleathman which are always a treat. We also had a lot of support during recording sessions from the good folks at Fitzrovia Post Studios in London – several of whom had been fans of the show during childhood, and one of whom was quite in awe of what the original production team had achieved all those years ago! (“But…but how did they do that shot without CGI?”)

(And apologies to the many many people that I really wanted to get involved with this set in some capacity or another but just didn’t have time to get to!)

Fred McNamara: Have there been any particular restoration fixes that Thunderbirds has been crying out for in previous releases? Have there been some restoration surprises that you weren't expecting?

Chris Dale: As I said above, these current ITV masters do come with some inherent minor picture issues, although certainly nothing to distract from the enjoyment of an episode. These vary from certain scenes being zoomed in to cover an issue on the edge of frame (most notably on Security Hazard, when after the opening titles the first three minutes of the episode is zoomed in) to minor film defects that weren’t caught when these masters were made (like Thunderbird 2’s tail gaining a pink splodge for a single frame during her launch sequence in one episode, which then appeared in multiple episodes since when these masters were created that shot was copied and pasted into almost every episode in which the launch featured to save restoration time).

Thanks to having access to the LTOs, we can see how those problem sections looked on the original film elements, work out what was done previously and why, and make a decision as to what to do with that particular shot for our release (which is always ‘make it look how it was broadcast in the Sixties’). Thankfully, in 99% of cases we’ve able to make the fix we wanted thanks to the LTOs. Infamously there was a shot of the Fireflash taking off which only appears in the episode Operation Crash-Dive which in these masters had been replaced with a similar one from Trapped in the Sky, and once we had access to the LTOs putting that right became the very fix we did (as already seen on the Thunderbirds Super Space Theatre Blu-ray set).

Another thing that was on our list to address was the ‘series two clouds’, which have been inconsistent across previous releases. For those who don’t know, the cloud image seen in the background on the opening titles of the six series two episodes differs from that seen in series one; it’s the same image, but airbrushed to make the clouds look darker and heavier. The ITV masters had standardised the clouds across all 32 episodes, and so the series two episodes featured the series one clouds (despite the correct 1966 copyright date). This has been an issue going back to the DVDs, where for some reason the series two episodes opened with a mix of series one clouds and series two clouds – or sometimes only series one clouds with their 1964 copyright date! Fortunately the LTOs offered us the chance to present the six series two episodes with their correct clouds, and it’s probably the definitive example of us taking great pains to get right something that most people wouldn’t notice or care about.

Speaking personally, the one thing that most surprised me was on the opening titles of Attack of the Alligators!, where the 'Filmed in Supermarionation' caption doesn’t wipe out from centre as in all the other episodes, but just suddenly appears on the screen. I assumed it was an error when I saw it on the test disc, having forgotten that it looked like that on the DVDs too, but no; that’s how it is on the original film materials for this episode, so that’s how we’ve left it!

Fred McNamara: I imagine it's been a hugely rewarding (if exhausting!) experience to restore Thunderbirds to look and sound as perfect as possible. How has the experience been?

Chris Dale: Putting this release of Thunderbirds together has been a huge undertaking, so naturally there have been ups and downs. The ups have been the opportunity to finally get Thunderbirds out on Blu-ray in the UK in its original aspect ratio, which is something that has been long overdue. As someone who has known the show for a long time it’s also been really interesting to be taking a closer look at the materials involved as we’ve undertaken the journey of restoring the series, and see some things I’d never seen before.

It’s also been great fun to work on creating the various new special features for the set. Many will have already seen on ITVX the Thunderbirds at 60 documentary produced by Take the Shot Films, and I want to take a moment to praise the hard work and dedication of their entire team in putting that together. It was also a joy to create a little mini Thunderbirds episode of my own with Fabblebox, for which Justin and Lindsay Lee deserve huge thanks for going above and beyond in the puppet and visual departments.

We did reach out to surviving Thunderbirds crew members to be part of both the documentary and new episode commentaries, and did get very close to having some of them on board, but unfortunately it just didn’t pan out. So instead, when it came to the commentaries for this set, it seemed to make sense to include people who had worked on later incarnations of Thunderbirds - the stage show, the audios, the 50^th anniversary episodes and the live action movie – and so we have veterans of Thunderbirds projects of every decade from the 80s to the 2020s. Everyone was really happy to do it and shared great memories of both the original series and their own associations with those later productions. It was also great fun to bring in two veterans of many a Doctor Who commentary, 1980s companion actresses Sophie Aldred and Nicola Bryant, to geek out about Thunderbirds across two commentaries (they specifically asked to do more than one!), sharing their memories of watching the series as kids and celebrating their enduring love for it as adults.

At the same time, the project has had its downsides, chief among them being the delay that meant we missed our planned-for September release date by, well, a lot, for which I cannot apologise enough. We did try to be as transparent as possible in what we were doing (via the Podcast and YouTube videos) but with such complex and intricate work being undertaken, it was very difficult to pin down a precise date for a 2025 release. We definitely could have done a better job of keeping people informed as to where exactly in the process we were, although very often we didn’t say anything because we had nothing to say other than “work is proceeding” – which it was! But as someone who once had to wait 17 months on a £200+ pre-order for a Star Trek collectible without a word of an update, I really do understand the frustration when you’ve paid your money and it seems like nothing is happening. I can only apologise once again; we believe that the final set is worth the wait! I’m also really grateful to those who were gracious enough to say things like “I’d rather have it right than right now” – thank you for being so understanding!

Then there has been the other kind of online reaction, relating to the mere existence of this set from certain quarters. The unfortunate truth is there are people out there for whom no Blu-ray release of Thunderbirds of any kind (whether it came from Network ten years ago or Anderson Entertainment today or anyone else in the future) will ever be satisfactory. The show is that big, that legendary, that everyone knows exactly what such a set must be – and everyone’s idea differs from everyone else’s. And in the age of social media, people who feel our set is lacking can get their views on it out for all the world to see – before the set has even been released!

Having seen a lot of that stuff, I would like to address one question spotted in a YouTube comment which was; “well, what else are they changing?” As in, implying that we’re making changes where we feel that a shot doesn’t work or to correct a continuity error or similar. It’s absurd to even have to clarify this one, but here goes anyway; no changes have been made to these episodes that go outside the remit of correcting existing picture issues with these particular transfers.

Let’s take an example; the infamous shot of Scott Tracy in The Impostors where he says the words “you can say that again” without moving his lips. Whatever the reason that slipped into the finished episode, that is an error within the original production itself so we have done nothing to ‘fix’ it, nor was it ever on the cards that we would. It would have been pretty simple to find a similar shot where Scott’s lips were moving, or even worse used AI to make his lips move correctly during that shot, but that would have been going far outside our remit. See also; removing visible wires on the puppets, which is a definite no-no with us but which a surprising number of fans actually seem to want! (Also, to be clear, no AI has been employed anywhere in this process.)

So, we’ve not replaced the Fireflash landing sequence with the Odessa steps sequence from Battleship Potemkin. Thunderbird 2 is not now bright pink, none of the Tracy brothers have been digitally replaced by their CGI Thunderbirds are Go incarnations, and nobody’s written ‘this is a fake’ in felt tip on the back of Braquasso’s Portrait of Gazelle. What this team has done is what we were asked to do; assemble the best possible presentation of these particular masters of Thunderbirds for a UK Blu-ray release, in the same way that other regions have already had, but with known defects and issues corrected to the best of our ability. Everyone involved has worked very long and very hard on that, and I hope that it shows in the final product.

Fred McNamara: Looking ahead to the rest of this year, what else can we expect from Anderson Entertainment’s home media output?

Chris Dale: Well, we have the already announced boxset of Captain Scarlet Super Space Theatre movies to come (which is being worked on right now) and hopefully there’ll be another SST release before the end of 2026. A Blu-ray re-release of New Captain Scarlet is also coming in the first half of this year, this time with its original opening and closing titles and original 5.1 soundtrack intact, along with some new (very) special features! We also have a couple of Blu-ray debuts on the way, and our friends at Silver Salt are scanning film elements for one of those releases even as we speak! They’ll also be bringing us more 4K episodes later in the year… and perhaps we may have one or two more surprises along the way!

Prepare for the ultimate International Rescue experience with the Thunderbirds 60th Anniversary Collectors Edition Blu-ray! The boxset will be blasting off towards Anderfans next month - Thunderbirds are definitely go!

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