Forced Perspective

The Ark
The Ark

The other day I watched a 1966 Doctor Who story called The Ark. It’s easy to look at a TV show that old and laugh at the stilted acting, rubber monsters and crude effects. But given the archaic and draconian conditions the series was made under back then, I can only admire the creativity displayed by the director and his team in visualising a script which was scarcely less demanding than a contemporary Who story.

Studio floor plan from the very first episode of Doctor Who, showing camera positions (coloured circles)
Studio floor plan from the very first episode of Doctor Who, showing camera positions (coloured circles)

In the sixties, each Doctor Who episode was recorded virtually as live on a Friday evening, following a week of rehearsals. BBC rules strictly limited the number of times the crew could stop taping during the 90 minute recording session, which was to produce a 22 minute episode. Five cameras would glide around the tightly-packed sets in a carefully choroegraphed dance, with the vision mixer cutting between them in real-time as per the director’s shooting script. (Interesting side note: some of Terminator 2 was shot in a very similar fashion to maximise the number of angles captured in a day.) It’s no wonder that fluffed lines and camera wobbles occasionally marred the show, as there was rarely time for re-takes.

But what’s really hard for anyone with a basic knowledge of visual effects to get their head around today is that, until the Jon Pertwee era began in 1970, there was no chromakey (a.ka. blue- or green-screening) in Doctor Who. Just think about that for a moment: you have to make a science fiction programme without any electronic means of merging two images together, simple dissolves excepted.

Setting up a foreground miniature for a later Who story, Inferno (1970)
Setting up a foreground miniature for a later Who story, Inferno (1970)

So the pioneers behind those early years of Doctor Who had to be particularly creative when when they wanted to combine miniatures with live action. One of the ways they did this in The Ark was through forced perspective.

Forced perspective is an optical illusion, a trick of scale. We’ve all seen holiday photos where a friend or relative appears to be holding up the Eiffel Tower or the Leaning Tower of Pisa. The exact same technique can be used to put miniature spaceships into a full-scale live action scene.

In these frames from The Ark, two miniature landing craft are lowered into the background before the camera pans to a full-size craft in the foreground:

The camera pans from a miniature descending in the background to a full-scale craft in the foreground.
The camera pans from a miniature descending in the background to a full-scale craft in the foreground.

And in these later frames, another miniature craft is placed much closer to the camera than the Monoid (a.k.a. a man in a rubber suit). The miniature craft takes off, pulled up on a wire I presume – a feat which time, money and safety would have rendered impossible with the full-size prop:

The camera pulls focus from a foreground miniature taking off to an actor in the background. A greater depth of field would have made the shot more convincing, but  the principle is sound.
The camera pulls focus from a foreground miniature taking off to an actor in the background. A greater depth of field would have made the shot more convincing, but the principle is sound.

Of course, Doctor Who was not by any means the first show to use forced perspective, nor was it the last. This nineties documentary provides a fascinating look at the forced perspective work in the Christopher Guest remake of Attack of the 50 Ft. Woman, and other films…

And Peter Jackson famously re-invented forced perspective cinematography for the Lord of the Rings trilogy, when his VFX team figured out a way to maintain the illusion during camera moves, by sliding one of the actors around on a motion control platform…

So remember to consider all your options, even the oldest tricks in the book, when you’re planning the VFX for your next movie.

Forced Perspective

The Miniature Effects of “The Day of the Doctor”

The cannon miniature
The cannon miniature

The fiftieth anniversary special of Doctor Who has been lauded for its cinema quality FX; indeed, I saw it in a cinema and at no point did I feel like I was just watching a TV show on a big screen. The Time War sequence was particularly impressive, and in amongst the CGI and special effects you may be surprised to learn there were some miniature effects which helped to up the ante. These were created by Mike Tucker and his team at The Model Unit, who a few years back did such a brilliant job of building the Wooden Swordsman for my Dark Side of the Earth pilot. This press release from the Model Unit reveals their contribution and how it was done.

The Model Unit’s involvement in Doctor Who: Day of the Doctor was for the Time War section of this historic episode, providing several cutaways of the Time Lord staser cannon (including its destruction) and a longer sequence showing John Hurt’s TARDIS crashing through a wall and destroying several Daleks that are unlucky enough to be in its path.

Model Unit supervisor Mike Tucker working on the Wooden Swordsman for The Dark Side of the Earth back in 2008
Model Unit supervisor Mike Tucker working on the Wooden Swordsman for The Dark Side of the Earth back in 2008

Following an initial discussion with producer Marcus Wilson to establish the sort of shots that might be needed Miniature Effects Supervisor Mike Tucker met up with stereo supervisors Adam Sculthorp and David Wigram to work through the practicalities of shooting high speed miniature effects sequences in 3D – a first for a British television drama production.

A proof of concept test utilising an existing miniature established that the models shouldn’t be smaller than 1/6th scale, and ideally at 1⁄4 scale. Further research established that the miniature effects sequences for the Martin Scorsase movie ‘Hugo’ had been done at 1⁄4 scale and with the same Alexa high speed camera rigs that we were planning to use, and so we were able to proceed with a certain amount of confidence that what we were about to do was realistically achievable.

Blowing up the cannon
Blowing up the cannon

With a five-week lead-time and a two-day shoot in Cardiff in April of this year model construction was split between several Model Unit regulars. Alan ‘Rocky’ Marshal was given the task of constructing the staser cannon, Nick Kool took on the TARDIS model and associated rigs and Colin Mapson worked with new recruit Paul Jarvis on the ruined Arcadian buildings and breakaway wall sections.

In a nod to past effects sequences, the Dalek miniatures were achieved in the time honoured way by utilising off-the-shelf toys (in this case the 18 inch voice- interactive toys that had been produced by Character Options a few years back), albeit with a few careful modifications in order to match them more closely to the actual props. Further detail was added to the interiors, including a scaled model of the mutant creature.

Model Unit DoP Peter Tyler worked closely with main unit DoP Neville Kidd to establishing a lighting design for the miniatures as, due to camera rig availability, we were shooting our miniatures in advance of the live action unit – a complete reversal of how things are usually done.

Close collaboration was also needed with the production design team with Mike and assistant art director Richard Hardy constantly swapping notes about the final design details of both Time Lord machinery and architecture to ensure a seamless blend with the location.

Day one of the shoot concentrated on the shooting of the cannon allowing the more complex rig of the TARDIS to be set up and tested, whilst the second day took in several takes of the TARDIS shots. The 1⁄4 scale TARDIS miniature was fixed to a steel rig mounted on a trolley system that allowed us to fire it at the wall using bungee cord.

Filming the Tardis breaking through the wall
Filming the Tardis breaking through the wall

Two takes of each set up were shot on two high speed Alexa stereo rigs shooting at 120fps.

Mike and his crew watched the completed episode at the Doctor Who Celebration at Excel with an audience of 2000 fans.

Visit The Model Unit’s website at www.themodelunit.co.uk

The Miniature Effects of “The Day of the Doctor”

Flog It!

Thanks to everyone who’s sponsored Stop/Eject so far, and also to everyone who’s shared and forwarded the call for sponsors. It’s been a great start to the crowd funding campaign.

Paul Martin
Flog It! presenter Paul Martin, a favourite with the senior ladies

The BBC’s Flog It! programme came to Hereford Cathedral yesterday, and since they were looking for stewards I decided to sign up. I’ve been a filmmaker for twelve years but I have almost no experience of broadcast TV, so this was a good opportunity to dip my toe into a different section of the industry.

If, like me, you’ve never seen Flog It! it seems to be exactly the same as Antiques Roadshow only they take your stuff to an auction at the end and sell it. Yesterday was a valuation day, meaning members of the public show up with the tat from their attic and a few will discover they were sitting on a nice little nest egg. Any items whose owners wished them to be sold would then be packaged up and sent off to auction at a later date.

The day kicked off around 7am with the usual rearranging of chairs and tables, unloading of vans and setting-up of the green room. Representing the cathedral was Dominic Harbour, who I last worked with back in 2003 when we filmed a couple of scenes from Soul Searcher in the Chained Library. (Veteran blog followers may wonder at his ever letting me back into the building.)

Filming the queue with a crane
Filming the queue with a crane

Filming was meant to begin at 9am with shots of the huge crowd waiting outside, but only about fifteen Herefordians had shown up so things were delayed for a while as we waited for people to get up. It actually wasn’t long before the queue was quite impressive – almost as impressive as the jib which was being used to film it and the speed with which this jib’s two man crew could move it and set it up. At this point my job was to stop passers-by from wandering into shot. The very first person I stopped and asked to walk around the back of the jib turned out to be one of the presenters – well done, Neil.

When the doors opened, us stewards had to lead the throng into an elaborate snaking queue which, at its peak, would represent a three hour wait for the dollar-eyed hopefuls. Once that was up and running, my job was to stand at the door and ask people entering if they were here for Flog It! (since the cathedral was still open to the public as normal) and if they were then to hand them an information sheet and apologetically point them towards the very back of the queue. It made me weep for the soul of humanity how many people were dull-witted enough to answer the question “Are you here for Flog It?” with “How much can I get for my wife?” Anyway, this job wasn’t very demanding and I was able to observe the shooting MO.

A view from behind the cameras
A view from behind the cameras

The crew had obviously done this many times and they had their system down pat. The front part of the queue formed a horseshoe around three sides of the main open space which was evenly lit with four 1.2K HMIs bounced off large polyboards. (Flog It! banners hid all the stands from the cameras.) This area was treated like a three-walled studio set. The cameras always stayed at the “fourth wall” end, where two or three kinoflos provided extra kick for the foreground tables. At these tables the show’s resident experts were filmed discussing items with their owners. This meant no re-lighting, apart from a bit of moveable fill which was provided by handheld or camera-mounted LED lights. In the background, two further 1.2K HMIs were angled up at the roof and attractive gubbins of probable religious significance around the altar. Job’s a good ‘un.

HMIs bounced off polyboards provided the main light source
HMIs bounced off polyboards provided the main light source

I was surprised at the number of cameras in use – five or six split into three units each with its own director and support crew. Two units were constantly shooting valuations at the aforementioned tables, while the third was at the other end of the cathedral shooting other valuations which had been picked out by the production team as particularly interesting.

At lunchtime I got a bit of a shock by how civilised the arrangements were. On low budget films I’m used to half a slice of pizza out the back of someone’s car, but this being a BBC production we were treated to hot cottage pie with steamed veg and bread at proper tables with real plates and cutlery and nicely folded napkins.

Ray Bullock Jnr. during filming in the Chained Library for Soul Searcher
Ray Bullock Jnr. during filming in the Chained Library for Soul Searcher

At 4:15pm we derigged in the cathedral to make way for evensong and moved everything into the narrow museum area leading to the Mappa Mundi exhibit and Chained Library. Here several more valuations were filmed and I was called upon to sit in the background of shot to fill up the frame. I was also put on tea and coffee duty around this time. To deliver the drinks to the unit at the back of the museum area I first had to get past the other two units, which involved a wait of several minutes at each one for a break in recording, like city traffic lights.

Filming wrapped a little after 6pm and after helping carry stuff back to the vans and put the cathedral’s furniture back where it had come from I bade goodnight to all and sundry and headed home.

It’s a long time since I’ve been right at the bottom of the crew structure, but it was a great experience – everyone was really friendly – and I was reminded of a few things I learnt earlier in my career about how to make a good impression as a runner. So here are my top tips:

  1. Get the tea and coffee orders right. Write it all down, including names, and then transfer that info to the polystyrene cup when you’re making the drinks so they’re easy to distribute. If there’s any chocolate around distribute that too. It’s always good for people to associate you with receiving tasty snacks.
  2. Your tasks will invariably be boring but complaining about this is a definite no-no. Make use of the time to observe what the crew are doing – but not to the detriment of carrying out your task.
  3. Make sure you’re projecting “keen and eager” at all times. Don’t dawdle eating your lunch and get back to the action as soon as your plate’s clear.
  4. If you have to walk in front of a camera (not while it’s rolling of course) remember to say “crossing” as a courtesy to the camera op.
  5. If there’s an opportunity to stay a bit later than most other people and help load those last few cases into the van when everyone’s knackered, do it and you’ll be remembered with warm feelings.
Flog It!