Introduction to Motion Control: An IMIS event

Most of us remember the scene of Harry’s arrival at Hogwarts across the Great Lake with Hagrid, as the castle looms out at us from the darkness. Or have that legendary image in our minds of the Imperial Star Destroyer gliding ominously through deep space in Star Wars IV: A New Hope. But we also have most likely seen any of those commercials in which leaves of lettuce, slices of cheese and tomato and pieces of chicken fall exactly in place on top of a loaf of bread in slow motion. Funnily enough, all of these have something in common: they have been filmed using motion control.

What Is Motion Control?

The guys from Mark Roberts Motion Control, Peter Rush and Dorian Culmer, were there to tell us all about it. Motion control is a means to create difficult or “impossible” camera movements and special effects by accurately controlling the trajectory of the camera. Cameras are mounted onto robotic rigs controlled by a piece of software, and they’re able to move at very high speed with incredible precision. Therefore, the same movement can be repeated again and again, for example, to generate special and visual effects.

Although it seems like a pretty modern development, motion control actually started before digital times. Around the 80s, there was a very busy scene in London in particular, to create everything that wasn’t digital. As machines and skills improved in this area, they started filming models – which is how the previously mentioned Harry Potter and Star Wars scenes were made. Models were the main reasons for motion control; first they would film the model, and then they would integrate it with a background and other elements to create a scene.

London became the centre for commercials in the 80s and the 90s, with many big-time directors today, eventually moving on from commercials to film. A higher demand for fast machines surged, machines that could shoot a commercial in 1 or 2 days, or that could film 3 to 4 movements per day. This requirement was different of that in Hollywood, and it was Mark Roberts who started meeting this demand by creating these machines. The first one of the notably mobile machines was called “Cyclops”, which is still a company staple today, capable of filming 3 meters per second with great accuracy using high-end cameras such as the RED Dragon, flawlessly shooting in 6K.

Uses Of Motion Control

Motion control has countless uses, the main ones focussing on VFX creation and live action. Since the camera can follow exactly the same very precise path repeatedly, it is possible to get different layers (actors, background, foreground) that can be overlaid and matched together at the time of compositing. This can also be used to “clone” people, change foreground and background objects, for morphing – which is when one person transforms into another person or thing, a very popular use – or to put things together that couldn’t have possibly been filmed together.

Other uses within VFX include being capable of shooting a scene very accurately so that only one pass might be necessary in post – for example when the camera goes through a glass or an eyeball. It can also shoot forwards, backwards, change the scale (size of the movement) and the time of the movement. The latter is another very popular use, which is combined with compositing to create scaling shots – the most recent example is 2015’s Ant-Man. To create the main effect seen in the film, it is necessary to have exactly the same camera movement for the man and the background to later put them together, otherwise they wouldn’t match. Along the same lines, it is also possible to do scaling by taking footage that has been filmed without motion control, first by tracking the movement to create the initial camera path and then filming the foreground or background with the same path to put the scene together afterwards. Alongside with these, it is also widely used for VFX previsualisations.

Additional uses of motion control include high speed shots, with rigs that can film 4 metres per second (3 metres per second on tracks), which are popular with food commercials, since it can trigger other movements – this is how the ingredients fall on top of the bread. It is also utilised in animation – it is possible to create stop motion or go motion that have complex camera movements – in sports, such as the Olympic Games or Formula 1 and for space research.

Is Motion Control Necessary?

Sometimes it may seem that motion control is unnecessary. Why not fix it in post? Since the quality required in cinema features is an expensive and slow work path, it makes post-production for high resolution sequences also very expensive. It can also be very difficult when it comes to fixing incorrectly filmed VFX shots. Thus, it is normally more efficient to shoot correctly the first time using motion control rather than fixing it in post.

The one thing that motion control requires however, is lots of planning to be done properly. Therefore, the director usually gets together with the VFX Director and the DOP or Operator, and decides if it’s necessary, and if so, how to best work out the shots they need. The disadvantage is that most people aren’t actually aware or don’t know how long it takes to use motion control, or how much money they need to get it right properly. For this reason, if deciding to use motion control, it is best to get someone on board who is properly trained, knows the equipment required, how to use it and how long it will take. This way, the shoot will be properly planned and therefore the production will end up saving more by getting it properly done the first time, instead of wasting valuable resources such as time and money due to a wrong kit decision or last-minute changes.

The Third Act: The Grand Finale

So, you’ve reached the end. It’s time for your protagonist to give us their last sweeping wave before the curtain falls and the lights come back on.

Hopefully you’re planning on going out with a bang, but before you dust off your hands completely, there are a few things you should know.

What goes inside the third act?

The Resolution Stage

Final Confrontation: Victory or Defeat

Based on the resolution section of the script, this act is usually the shortest (between 20 and 30 pages) it’s the final twist or metaphorical battle, and then the return to home or normality (though life for the main character will never be the same again–definition of a successful character arc).

This is what Snyder would call the Break Into Three. It’s the moment we’ve all been waiting for. Here your story will reach its final twist, the moment everyone’s been waiting for since you unleashed the inciting incident. It’s the climax of the story, the final battle. Your character has been pursuing a goal throughout the entire second act, and now they’ll either get it, or they’ll change the goal to coordinate better with the theme, i.e. the moral lesson they’ve learnt. If you ended the second act on a low point, now it’s time for your character to get back off the ground and re-group.

During the final confrontation, the main character is forced to reexamine their beliefs. They will put everything she or he has learnt over the course of the film to good use to defeat the antagonist, always incorporating and exposing the nugget of truth, the film’s overall theme. In the Hunger Games, Katniss stops obeying the game’s rules, and starts to fight back herself, using what politics she’s learnt during the first and second act. Instead of murdering Peeta, she tricks the capitol into thinking they’d rather kill themselves by eating poisonous berries, when in fact it’s a survival tactic.

Character Arc in the Third Act

Another determining factor of the third act is the character, unlike in the second act where they’re surrounded by other characters, will mostly work alone (in the absence of their mentor) against the antagonist. In the Silence of the Lambs, Clarice has to stop Buffalo Bill by herself, because the police have gone to the wrong place and Hannibal, her “mentor” didn’t hang about long to help her.

Basically, your audience has witnessed your character go through hell and back, and now they’re waiting for the reassurance that it wasn’t all for nothing, that your character has beaten the odds and grown because of it, developed in some positive way.

Normally, this character arc is represented through a mirror effect. For example, if the character’s flaw in the beginning was to lie or connive, in the third act the character will do exactly the opposite of his/her previous nature.

Denouement (the Afterward)

The resolution at the very end will give us a glimpse of the new status quo, or the state of your protagonist’s life after all has been said and done. In the Hunger Games, the ending isn’t Katniss and Peeta defying the capitol with the berries, it’s Katniss and Peeta back in District 12 as the crowning victors, hinting at the change in Katniss as she struggles to familiarize herself with her surroundings.

This–very short–section ties up any of the film’s loose ends and answers lingering questions about the plotline.

It’s Blake Snyder’s final image. It’s what he calls the opposite of the opening image, the final shot that demonstrates the absolute mirror change that has occurred. In Pride and Prejudice, the opening image has Lizzie walking through the grounds of her father’s cottage, alone with her head stuck in a book. One of the final images of this film sees her walking at dawn, still alone, but then Darcy comes striding out the mist towards her. She’s no longer alone, and more than that, she’s completely changed since the opening. She’s less proud and quick to judge.

Script to Screen

Scripts which transition into films will most certainly go through test screenings to gauge the audience reaction so that producers can decide whether or not they’ll be a box office hit. Third acts and character arcs are often changed as a result of a negative test screening.  

In Blade Runner, Ridley Scott was pressured to change Ford’s Character into a more ironic, upbeat version than his original, darker self. This eventually affected the ending, in which the original dark ending was changed into a more upbeat one to reflect Ford’s character. Instead of dooming the entire human race, the ending scene touches on a hopeful ending in the sunshine.

In Pretty in Pink, according to the original script, Andie’s character arc saw her develop feelings for Duckie, whose own unrequited love for her form the emotional bulk of the film. But when tested on audiences, this romantic development wasn’t at all favoured, and so Blane and Andie end up together. Receiving mixed reviews, some thought this made Andie’s character slightly more realistic and less fickle, because she continues to like the same character she did in the beginning, and still appreciates Duckie’s relationship.

Hancock was originally a script entitled, Tonight, he comes, and Hancock’s character was much darker, dabbling between alcoholism and depression. The end result, produced nearly a decade after the script was written, became a much lighter, quirkier version than its predecessor, all for story purpose.