Here is a fantastic article about some of the Special Effects techniques used in Star Wars The Empire Strikes Back, from a long our of print edition of Cinefex Magazine.
Of Ice Planets, Bog Planets and Cities in the Sky
Richard Edlund discusses the technological advances that enabled Industrial Light and Magic to wrest the Star Wars saga from the matte-line haven of outer space and project it into even more optically foreboding environments.
Interview by Don Shay
If ever a film was destined for sequeldom, Star Wars was it. George Lucas' whirlwind venture into ancient times and distant galaxies struck an immediate and resounding note upon its release in 1977, prompting audiences worldwide to surrender more than $400,000,000 at the boxoffice in direct tribute to the picture's unyielding capacity to enthrall and entertain. Even before the film was released, however, Lucas had envisioned it as but one chapter in an ongoing saga, and within months had launched into preparation of a second installment, The Empire Strikes Back.
Star Wars — rechristened A New Hope in belated acknowledgment of its place in the overall Star Wars opus — was filmed primarily at the sprawling EMI Elstree Studios near London. Its voluminous special effects, however, were engineered and executed thousands of miles away at Industrial Light and Magic, an all-encompassing optical facility formed under the direction of effects supervisor John Dykstra (2:50-71) specifically for that purpose. A key member of Dykstra's ILM team was first effects cameraman Richard Edlund.
Edlund brought to the production a diversified background in motion picture and special effects photography. Born in Eargo, north Dakota, he gained a basic knowledge of photographic systems and techniques in the U.S. Navy and at the University of Southern California. Me spent four subsequent years in the employ of his longtime friend and mentor Joseph Westheimer, working on television commercials and on primitive opticals for series such as The Outer Limits, The Twilight Zone and Star Trek. Ultimately he left the firm to work unencumbered as a freelance still photographer and promotional filmmaker for a number of prominent rock groups. After that, he joined Robert Abel and Associates where his talents were put to use on a variety of sixty-second extravaganzas which for years were the Abel trademark in television commercials.
Edlund was hired onto the Star Wars effects unit in 1975, and spent the next two years utilizing Industrial Light and Magic's innovative motion control technology in the photography of spacecraft miniatures. When effects work on Star Wars was completed, the ILM unit remained basically intact throughout the early segments of Battlestar Qalactica until John Dykstra withdrew from the series and Universal established its own in-house effects capability. Edlund then photographed the miniature effects sequences for The China Syndrome before responding to the call to be special effects supervisor for The Empire Strikes Back. Implicit in the offer, however, was the proviso that Industrial Light and Magic be moved from its original site in Van Nuys to the Lucasfilm base camp north of San Francisco.
Preferring a more detached role than the one he had essayed on the first Star Wars outing, George Lucas relinquished directorial reins to Irvin Kershner, electing instead to be executive producer. In addition to the extensive studio work — much of it filmed on one of the world's largest soundstages, constructed especially at EMI Elstree to house the oversize sets for The Empire Strikes Back — Kershner also led a subzero shooting expedition onto the Mardangerjokulen Glacier in Norway. Edlund, meanwhile, was engaged in a two-year drive to organize and execute the elaborate special effects required for the film. Since Lucas had perceived the need to liberate his saga from space-bound stagnation, many elaborate effects sequences had been incorporated in settings and environments which would have been essentially impossible to realize with the technology already available from the earlier film. Clearly, Edlund and his associates had their work cut out for them.
How did you go about reestablishing Industrial Light and Magic in Marin County?
There were about six or eight of us from the original effects crew that decided to follow the Star Wars saga into northern California — actually more than that, but about six or eight in the key staff positions. Dennis Muren and I had split most of the model photography in Star Wars and we decided that we would work together again on Empire — he became the director of photography. I was able to convince Bruce Nicholson that he could, and should, become head of the optical department. Peter Kuran became head of our animation and rotoscope department. Lome Peterson, our model shop chief, and Steve Gawley, our model shop foreman, were also veterans. Phil Tippet and Jon Berg took on the much expanded stop-motion work in Empire. And then, in head of our electronics shop we had Jerry Jeffress. So we had kind of a basic core of people with a lot of corporate knowledge and a solid working relationship already established.
The facility itself was a new building — empty like the old Industrial Light and Magic was when we first started gearing up for Star Wars. We did bring along with us some of the original equipment, though, including the main tracking camera, the matte camera, and an optical printer. But that still left a lot of serious holes in our equipment inventory; so one of my first concerns was designing and getting the rest of the equipment we'd need constructed, and also restaffing the entire facility.
Photo: Like its predecessor, The Empire Strikes Back was filmed primarily in England. Its special effects, however, were produced at Industrial Light and Magic in San Anselmo, California. In charge of the more than four hundred optical effects shots in the picture was Star Wars veteran Richard Edlund.Nearly two years were devoted to equipping the ILM effects facility, assembling a crew, and producing the required footage.
You and Brian Johnson shared supervisory credit for special visual effects. How did you interface?
Brian's forte is in getting the organization together to produce all the physical effects that are done during the principal photography. My expertise is in photographic effects involving miniatures, motion control photography, slow-motion, and traveling matte work — the technical aspects of all these weird processes. So I was in charge of the Industrial Light and Magic facility. Brian was there, and he contributed during that period, but he was really more involved in what was happening in London and what was happening in Norway — fog and explosions and rigs to cause weird things to happen. He was also in charge of rebuilding R2-D2 and getting it to respond properly to radio control signals.
The two main projects I started with were the design and construction of a special optical printer to do our composites and a high-speed VistaVision camera. VistaVision is a large format 35mm system that feeds film through the camera horizontally rather than vertically, so you end up with an image about twice the size of normal 35. Since all the material we shoot has to be duplicated, we've found that you don't lose nearly as much quality if you start with a big negative. I chose VistaVision format over 65mm, because 35mm film stock is easier to work with and the equipment is far less cumbersome. But there were no VistaVision cameras anywhere that would run over thirty-six or forty frames a second, even if you were pushing it. So we had to construct one, and 1 commissioned the Mitchell Camera Corporation to build us the movement.
At the same time, I was working with George Randle on getting the cameras and movements built for the optical printer, and with David Grafton who was designing the special optics. We had to build our own printer from scratch, because the standard optical printers that you find in this business are really geared more for your basic fades and dissolves and blowups and things like that — not for intricate composite photography. As a result, they were simply not adequate for the quality of work we had in mind.
The exciting thing about this project, from the standpoint of equipment and technique, was that it would be an on going situation and not one that would be formed for just one production and then disbanded. So we're sort of building a monument here. All the equipment we have is designed in such a way that it is totally interfaceable, and the grand design of all the electronics equipment — which is Jerry Jeffress' forte — is based on the concept that everything we make now is computer-controlled. Therefore, it is malleable in that you can change the function of it by reprogramming the computer. The composite printer, for example, has a very complex electronics system which is based on this principal, so it's not likely to become obsolete nearly as fast. If you have a piece of equipment which you want to perform some function which it didn't need to do before, instead of tearing into the machine and changing a bunch of wires and then taking it off-line for two weeks while you debug it, you can do it all in the electronics department. Then all you have to do is take a new chip and plug it into the system and you're down for maybe five minutes.
Photos: Richard Edlund examines the rebel cruiser model while executive producer George Lucas visualizes a potential camera angle. Although Lucas deferred directorial chores on his sequel to Irvin Kerschner, he remained intimately involved in the production — paying particular attention to the activities at ILM. / Effects unit art director Joe Johnston prepares a model nebula for photography. The swirling star formation was filmed with a slight rotation and incorporated into the final sequence. / The skeletal form of Darth Vader's personal star destroyer is fitted with neon tubing by model maker Charles Bailey. On camera, the eight-foot vessel dwarfed all others in the Imperial fleet. / Toxic materials are commonplace in miniature work, necessitating protective gear which transforms the model shop into something resembling a surrealistic operating room. / Assbtant cameraman Rich Eichter watches as Scott Marshall and model supervisor Lome Peterson add finishing touches on an oversize section of a star destroyer conning tower to which the Millennium Falcon affbces itself.
What are the particular capabilities of your optical printer ?
Well, what sets it apart right away is the fact that it is a beamsplitter printer with four projector heads. Most optical printers have only two. With four heads you can put a shot together in one pass. The projectors are mounted together in pairs. One pair is mounted inline with the camera; the other is mounted perpendicular. The images from both pairs are combined in a beamsplitter and photographed in the camera. So you can put your foreground and its matte in one leg, the background and its matte in the other, position the mattes until they fit properly, and then put the shot together in a single pass. That's one advantage. Another is that it increases the throughput of the machine — even if you use only one leg at a time — because you can be printing on one leg while you're putting up another element in the other. Obviously, that gave us more printer time, which therefore allowed us to put more shots together in the time we had. Every shot you see in The Empire Strikes Back that was done at Industrial Light and Magic went through that printer.
But what's really significant about that machine is the optics. Generally, the optical system on an aerial printer is sort of resolution-limited. In other words, what you put in the far head is not as sharp as what you put in the front head because of the limitations of the general optical system. Our printer has a specially designed optical system which is so sharp that you can use either head without worrying about any image degradation. Therefore our mattes are not distorted by the inadequate optical path which until now has been industry standard. The standard optical printer does not use telecentric lenses. A telecentric lens emits parallel bundles of light. If your lens is not telecentric, in order to maintain equal illumination across the image you have to recollect the light by means of a field lens near the image. You may have a relay lens which is capable of a hundred and fifty line-pairs per millimeter, but when you put a field lens in there you lose about half that resolution and you also introduce chromatic and geometrical distortions. But since you must have that field lens in there to collect the light again, you're caught between the devil and the deep blue sea. So when we set about building our own printer, we decided the best way to do it was to design the lenses first, because in the final analysis it's the optical properties of the printer that are the most important. Once we had the optical system, we could wrap the rest of the printer around it.
I had to stick my neck out a long way because it was a prototype and was going to cost a half million dollars or more, but I was convinced that we needed it in order to put the picture together and it would be something we could use for many years to come: so it was a capital investment. It finally took us about a year to build it, but it worked amazingly well right from the start — the optical system exceeded even my expectations. In fact, in quite a few of the shots we had to actually degrade the composite image in order for it to fit in properly with the background photography. So that printer was certainly a major contribution to the film, and it's the only one of its kind in the world.
Photos: Paul Huston and Ease Owyeung add detailing to Darth Vader's flagship. / The three-and-a-half foot diameter Millennium falcon used in Star Wars was replaced to a large extent by a smaller, two-foot version that was substantially lighter in weight and more maneuverable. Mike Eulmer adds airbrush detail to the new spacecraft. / Phil Tippet meticulously animates a miniature tauntaun and correspondingly-scaled Luke Sky walker for the opening sequence in the film. Foreground miniatures and background paintings were used for most of the stop-action shots, which were then intercut with footage employing live actors and a full-scale mechanical tauntaun. / Model shop foreman Steve Gawley works on the rebel snowspeeder — a small, two-man craft used on the ice planet, Hoth. / An Imperial star destroyer under construction.
Would you say that the singular lack of matte lines in The Empire Strikes Back was a function of this new printer?
That and a number of other things. The fact that we have distortion-free relay optics so that the mattes can fit the object perfectly is certainly a factor. But generating those mattes is another matter in itself, and we have become extremely proficient with bluescreen. The original idea on Star Wars was to shoot everything front- and back-lit since the motion control cameras were capable of doing an identical double pass. But I didn't believe that was feasible because you can't do a doublepass matte and get the leading edge of a moving object to have the same transparency as the trailing edge. It would work out okay if everything you were shooting was moving slowly against a star background, but if you get into a situation where you have a lot of blur — and there was necessarily going to be a lot of blur in Star Wars, because there was a lot of fast action — it's an entirely different matter. When you look at a single frame of movie film, it's surprising to see how much blur there is in it, especially when there's something traveling right towards you and it's filling the frame. I mean, the last few frames of that image are nothing but a blur, and the fact that they are means that they have a certain amount of transparency. If you have a shot with an enormous amount of blur, and you extract a high-contrast matte from that shot — which is what you do with the doublepass method — the matte has a very limited gray scale and you end up with an opaque matte. As a result, your images do not have that transparency that makes them look real, and they tend to strobe. So I was extremely adamant that we go to bluescreen.
The fact that we did, though, was really quite an act of faith on George Lucas' part. Like all of us, he had seen a number of bluescreen shots with enormous ugly blue fringe matte lines around them, and to him that was representative of the system. And for a director to go to dailies and see his actors working in front of nothing but this totally unusable blue background is enough to induce acute states of paranoia — especially since, at the time none of us had much of a track record to fall back on. Now, I would be the last one to maintain that the bluescreen work in Star Wars was perfect. In fact, there are a lot of shots in Star Wars that make me cringe now. But we got away with it because they were all going by so fast. Very few of those shots lasted more than seventy-five frames, and a lot of them were less than twenty-four. Since then, we've been able to develop a lot more finesse. We wouldn't have been able to do a lot of the shots we had to do in Empire back during Star Wars, particularly all the matting we did over the snow battle scenes. In fact, in general terms, I'd say the composites in this picture were several orders of magnitude more difficult than the ones we had on the last picture.
You only matted over light areas in a couple of places in Star Wars — one where the Millennium falcon is peeing the Mos Eisley spaceport and another where you had an X-wing flying in over the jungle at the end. Matte lines were pretty evident in both of those shots. What enabled you to matte over white areas so well in The Empire Strikes Back? Was it strictly improved proficiency and the new printer, or did you make technological improvements in the bluescreen process as well?
We used basically the same system, for Star Wars we developed a fluorescent bluescreen that functioned on direct current rather than alternating. Therefore we could do highspeed photography without worrying about flicker problems. I believe it was the first fluorescent bluescreen. I may be wrong there — I've met five guys who've all told me they invented the blimp — but it was certainly the first large-scale bluescreen done
with direct current fluorescent bulbs. We made refinements on it for Empire, so we've now got a better blue: but it's basically about the same. The system for mounting the ship was something I developed back on Star Wars. We use a neon pylon which is color-balanced to the bluescreen so we can eliminate the need for rotoscoping the mounting rods out of the shot. We refined that a bit, too: but not much. I think we really hit on the simplest possible shape and the simplest possible technique for doing that in Star Wars; and to me, the simplest answer is generally the best. It's easier, it seems, to make things complicated than it is to make them simple.
Did you make any significant advances in motion control technology over what you had used in Star Wars?
Yes. Even though the system we used on Star Wars was quite fine — and functioned well with a few modifications even on this project — we have a new system with capabilities that far exceed the old one. Our basic philosophy of miniature preprogrammed photography is based on the concept that in real photographic situations, especially in battle circumstances, your camera movements are bound to have a certain amount of random motion. Therefore, in order to duplicate the feeling that what you're seeing is being photographed on-the-spot by a human and not by a machine, we program most of our camera moves manually with a joystick device. If you were to have an absolutely perfect move, it would have none of the irregularities that are characteristic of human action and it would really be rather an uninteresting shot. However, there are situations where a computergenerated, mathematically-perfect move is useful — like with titles or with a really short cut where it doesn't matter that it looks that way — and our system now has the capability of graphically plotting out each axis and doing that. So even though it's something that we don't use all the time, it does have its applications; and if we can aid the speed of production by utilizing the technique we'll do it. More often than not, though, it takes longer to produce a program mathematically than it does to actually go out there on the stage and turn knobs and screw around until it looks right. But the capability is there when we need it.
We also built a field-usable motion control system — with a reflex VistaVision camera, a special Mitchell gear head, and a tape data storage recorder — that you can use out on location to record pans and tilts and then repeat them later back on the stage.
Photos: A major effects sequence on Moth involved an attack on the rebel stronghold by five Imperial walking machines. Most of the walker footage employed three eighteen-inch models which were stop-motion animated by Phil Tippet and Jon Berg. A couple of shots, however, required walkers to fall over, and for these, a larger, four-foot model was constructed and filmed with a custom highspeed camera to maintain a sense of mass as the walkers collapsed. While Richard Edlund waits behind the camera, stage technician Ed Mirsch adjusts a breakaway wire rig and Jon Berg positions the feet. Model shop foreman Steve Gawley assists. Surgical masks were worn to avoid inhaling the baking soda which doubled as snow.
Is this like the system used on Close Encounters which allowed them to make camera moves on live actors and model saucers in the same scene?
This one's basically the same, but more streamlined. As it turned out, though, we weren't able to use it on the live-action footage, because it wasn't ready by the time the unit went on location. We'd already designed and built the camera for the unit — and that was shipped to Norway for use on the live-action shots we'd later be matting on — but the field recorder system was not complete at that point. After the location work was finished, the camera came back to our facility and Dennis used it to shoot just about all of the miniature stop-motion material.
All together, we had four motion control systems in use on Empire. We also had a matte department that we built up from scratch, a custom-built VistaVision-format Oxberry animation stand, a rotoscope camera, a garbage matte camera, and a half dozen or so other cameras. By the time we were in full swing, our once-empty facility was filled to capacity with all sorts of equipment and we had a crew of about ninety people.
The opening shot in Star Wars was a real grabber. Did you make an effort to duplicate its impact in The Empire Strikes Back?
Empire was going to open in the snow at first, but then somewhere along the way George decided he would rather have it start out in space. Certainly, the opening shot in this picture isn't as dynamic as the one in the original — but then it didn't need to be, really. The philosophy on the Star Wars shot was that this was going to be the first impression you were going to get of the picture. The effects were obviously going to be very much different from anything that had gone before. They were certainly a lot different from 2001, for example, where the effects shots were very ponderous and were on the screen for huge chunks of time and were done with enormous miniatures that took up entire sound stages. Well, we didn't have the luxury of being able to work that way. We had 365 shots to do and not a whole lot of time or money to spend on them. So instead of having miniatures that were fifty feet long, we had miniatures that were eighteen inches long, and we used speed to achieve our effect. That was kind of our style. I'm not sure if it was realistic or not, but it was stylistically integral — and it was convincing enough to prompt an astronaut that I met at a party once to tell me that he believed it all and was glued to his seat. An any rate, we wanted the opening shot in Star Wars to be so amazing that people would say: "My God! Look, it's still comingl It's enormous!" We wanted that first impression to be a positive one — one of awe — so everyone would immediately be satisfied with the look of the effects and the style of the effects and would then sit back and say: "Well, I've accepted that. Dow, let's get on with the story." We didn't have to concern ourselves with that going into the second one.
The film has some really innovative stop-motion work. Could you discuss the helicopter shot that swoops in over the running tauntaun?
That was Dennis Muren's piece de resistance; and I think it's one of the best shots in the picture from the standpoint of ingenuity. It was very well planned and very carefully executed, and a great deal of time went into it. The basic helicopter footage was shot with a Wesscam system, which is a special camera system that hangs off of a fancy helicopter and is gyrostabilized to take bounce and roll out of the picture. For that particular shot, it was gyrostabilized on two axes to stabilize the horizontal and the roll. The tilt wasjoysticked, so that as you flew into the shot you could tilt down onto a particular area. Once we had that footage, it was a matter of plotting points. Basically, you have to take features on the ground — and here there weren't very many — and then see how they change. There was a rock in the middle of the shot which was an important point, and there were certain ripples in the snow you could pick out if you got good at it. From those, we had to work out the geometry of what the actual move was, and then plot that on the Oxberry to find out just how far the camera moved in and how much it tilted — within pretty exact tolerances. It's like photo interpretation — plotting an airstrip that somebody shot flying over Cambodia, or something. Once we isolated that information, Dennis had to program the motion control system to reproduce — on the tauntaun — the exact amount of angular change that was going on during that helicopter shot. The tauntaun, meanwhile, had to be moving horizontally through the frame at a certain speed. Phil Tippet did that with stop-motion animation. Once the tauntaun was photographed with all the proper moves, Sam Comstock had to rephotograph it on the Oxberry and reduce the image down to the right size to fit the scene. Then, in addition to the basic elements, there were other things to contend with — like shadows under the tauntaun and, of course, mattes. So what you end up with is an extremely complex series of events, all of which have to be done just right, and there's no real way of telling if it's going to work until you see it all composited. So it was quite an accomplishment.
When you're working on a film like this, do you find yourself grading potential shots — either by degree of difficulty or importance — and then devoting your energy to them on some kind of a prioritized basis?
Well, certain shots you have to concentrate on more than others — that's just part of understanding the momentum of making a feature film. At the beginning of any project, you read the script and then you begin making storyboards. But while you're in the process of making your storyboards, you have to bear in mind that what you're coming up with has to be done, and it has to be done by one or more people using certain techniques and with certain equipment which is either available or under development. So it's a very complex matrix of actions, all of which have to be coordinated. Jim Bloom, who was the associate producer on the picture, was basically responsible for coordinating all of the activities at ILM. He set up the location shoot in Norway; but then when that was finished and the production moved on to England, he came back here and helped us by developing a production board and scheduling out all the shots.
Photos: The large-scale walker was used once again for an explosion shot triggered by Luke's tossing a detonating device inside the lumbering war machine. That explosion, and a subsequent larger one after the walker collapses, were also shot at high-speed. / Joe Johnston adds painted highlights to an oversize walker foot. / The oversize foot was mounted on a giant pipe rig and used to crush Luke's downed speeder. / The Millennium Falcon's pursuit through an asteroid field was punctuated by a daring dive into a giant cavern which turns out to be the interior of a monstrous space slug. Lome Peterson works on the mechanized jaw segment which begins to close just as the miniscule Falcon attempts its escape. / Earlier in the sequence, the ship makes a daredevil barnstorming run through the asteroid's treacherous chasms. Effects director of photography Dennis Muren films one segment of the dizzying passage. A layer of smoke in front of the camera serves as a diffusing agent. / Dennis Muren (left) prepares a motion control shot from the Millennium Falcon's point of view as it skims the asteroid's cratered surface.
I remember Lin Dunn coming out to ILM during the early days of Star Wars. He was there at the behest of 20th Century-Fox to sort of look us over, because nobody there really knew who we were or what we could do and they were banking on us to complete this multimillion dollar picture. Anyway, fox wanted some learned opinion, so they sent out Lin Dunn and Cecil Love — beloved deans of special effects — to look us over. And I remember Lin's very adamant advice: "I have no doubt that you guys can do the work, but what you really need here is somebody to help you schedule." So, yes, you have to prioritize and you have to keep evaluating things and making changes where necessary. And you have to know up front if some idea you have is going to take a long time to develop and execute. Like the walkers, for instance. I mean, never before had that kind of effort gone into a single stop-action sequence. We had several guys who worked for damn near a year on that — designing those things, building five or six of them, and then getting them all tweaked out and detailed. Then shooting them took maybe another two months.
Could you discuss that sequence a bit?
Dennis Muren did most of the photography — in fact, I think he did all of it except for the high-speed work which I shot. Jon Berg and Phil Tippet animated the snow walkers. As far as the stop-motion goes, Jon was chiefly involved in the design and animation of the walkers — although Phil did some of that animation as well — and Phil was chiefly responsible for the tauntaun. The walker sequence involved several different filming techniques. A large amount of it was shot using foreground miniature landscapes and painted backgrounds. We used about fifteen different background paintings in the walker sequence and the tauntaun shots. The largest was about thirty-five feet wide and twelve feet high, and the smallest was maybe four feet wide and two feet high. The walkers themselves were about a foot-and-a-half tall. The speeders flying around them were shot separately under motion control and matted in.
One of the shots that worked out rather nicely, I thought, is the one where Luke's speeder crashes into the snow. In the initial part of that scene — a POV shot out of the cockpit window — the speeder goes flying past one walker and then dives down almost to the point of impact, which is practically under the feet of one of the other walkers. What we wanted was to hold the shot all the way until the speeder actually hit the ground and then have snow flying up over the canopy. Well, that would be impossible to shoot in a stop-motion situation: so we did the shot in stop-motion all the way down until just before impact. Then we had our expert grip build a little luge rig for the camera. We called it that because the Olympic luge competition was going on at that time. It was sort of a sled with a plexiglass shield shaped like the speeder canopy, positioned in front of the camera. Then, with the camera at Luke's point of view, we smashed the whole rig into the snow. We used about thirty or forty frames of it, and we made a direct cut from the stop-motion footage to the luge so it looks like one continuous shot. The speeder goes in and snow flies up over the windshield. And it works, because you're not jarred by the cut at all. You're so caught up in Luke's situation that you don't even notice it.
That sounds somewhat similar to the point-of-view shot you did in Star Wars where you cut from a still photograph to live action as you come in over the Death Star and swoop down into the trench.
Right. I think that was a real successful shot, too. In fact, it's one of my favorite shots in Star Wars and one that drew some of our nicest compliments. The whole idea is to create an impression. You have to design and execute your shots in such a way
that your audience is swept along by the action and the drama and not disturbed by a flaw in the special effects. If you've done that, then you have a successful shot.
One of our most complex shots in the walker sequence was done with bluescreen matting — we had to use that technique whenever we had people composited into the scenes. This one particular shot showed a bunch of the rebel troops running toward the camera, retreating from the walkers which you can see approaching in the background. We started out with a plate shot on location in Norway that had the foreground action of the guys running forward. We took that, put it on a viewer, and made an exact tracing of the shot. From that, we could determine precisely at what angle the camera had been shooting and then duplicate that angle when we shot the miniature walkers. Once we had the proper perspective and the proper lenses and everything on the camera, we went ahead and shot the walkers — I think there were two of them — against bluescreen, and then matted them into the live photography. The only area that was problematic was how to make the feet look as though they were actually touching the ground. Obviously, if it doesn't look like these things are standing on the ground, your shot has failed. So Pete Kuran did what we call a grounding matte, which matched the two elements so the walkers' feet looked like they were indeed hitting the ground. Then, of course, we had speeders flying through and animated lasers zapping back and forth. So by the time we got all the elements for that shot and it went through editorial and optical, nearly every department at ILM had a hand in it.
Then there was an explosion that was done live on location with all kinds of debris and stuff flying about, and what we did was we matched a speeder's trajectory towards the spot where the explosion was going to occur and timed it so it would look as though the speeder went crashing into the ground and blew up.
how about your high-speed work in that sequence?
We used high-speed photography in several places where we had to convey an impression of great mass — for example, in the scenes where the walkers are toppling over. For those shots, we built a larger scale model of the walker, about four feet tall. Jon Berg and Tom St. Armand did a wonderful job on that, getting this enormous thing machined and built and ready to behave properly once the camera was rolling.
Was that model electronically operated?
No, it was all done by hidden wires and solenoids and getting the thing properly balanced so it would topple over just the way we wanted it to. The high-speed camera, though, wasn't ready until just about the time we were starting to shoot that stuff. When the movement was delivered to us it would run all right, but not at the speeds we needed — so we had to do a considerable amount of massaging. Making a camera movement go fast is just one of those things that I guess you could call a black art, because it's something that can't be readily taught. You have to learn from experience and fooling around and making mistakes. So it was a very complex and tedious process, and by the time we got the camera up to a speed we could get by with, we already had stuff waiting to be shot. There are formulas for sort of figuring out how fast a camera should run on high-speed shots, but normally I just go by what I've done in the past and what I think ought to work. Most of the high-speed stuff in Empire was shot at ninety-six frames per second because that was about all we could coax out of the system — we're reworking it now and I hope eventually to get it up to a hundred and fifty.
Anyway, the walker sequences were done stop-action with the smaller models, right up until the time they start to fall over — then we cut to the high-speed work. It involved a lot of very skillful manipulation to get them to topple over, and for the one shot where the thing gets roped by one of the speeders, we did about four or five high-speed takes with wind machines going and everything. And we got some pretty interesting variations. I think the one we finally used — where it kind of kicks up its heels and falls over sideways — is pretty funny, and I guess audiences like it because they always give it a good reaction. The other walker — the one that tumbles forward on its face and blows up — I shot with my own personal camera, which is a high-speed Mitchell that'll run at 175 frames per second. It's not VistaVision, though, so that one shot had to be anamorphic. But in this particular case, it was more important to have the speed than the image area because in order to get the pyrotechnics to look in scale you have to shoot them as fast as possible.
A majority of the high-speed shots were done with the painted backdrops, but we did do a few with bluescreen — for example, the shots where Luke shoots his magnetic line up onto the underbelly of one of the walkers and shimmies up. That was done high-speed in order to give the feet the apparent weight they should have. Another shot we did high-speed was the one where Luke's speeder gets crushed. For that, we had one large foot mounted on an enormous pipe rig that was built out of camera range: and we used a special model speeder made out of thin metal. An awful lot of work went into making that thing and detailing it out — so it was a one-shot deal. If you blow a take like that, the model makers aren't real happy.
Did you do high speed work anywhere else in the picture?
Yeah, we did the space slug in high-speed — that big thing that comes out of the hole in the asteroid and snaps at the Falcon. Also a lot of explosions. For those we rented the San Francisco Armory, which is an enormous drill hall over in the Mission district. We picked it because it was the biggest single room we could find anywhere that was unrestricted — the ceiling's a good eighty feet high. We constructed our own ceiling in there that was black and measured about a hundred feet long by sixty feet wide, and we photographed a whole bunch of explosions, about sixty feet off the ground, that were really quite large. We had five high-speed cameras going on each take, and we only had one jam on us in all that time. There were two VistaVision high speed cameras — my old favorite that I used to rent from Paramount that maxed out at seventy-two frames per second, and our new one that was shooting ninety-six. We also had three others shooting anamorphic, including Bruce Hill's high-speed camera that runs 360 frames per second. As a result, we have about the best library of explosions you could possibly imagine. We filmed in there for a couple of weeks and ended up with something like four hundred different explosion shots.
Then you just superimposed those explosions over whatever it was you wanted to blow up?
Well, we extracted mattes from them first; but basically, yes. There are a number of them in the asteroid sequence, and a couple that characterized the generator blowing up that are just seen through windows. We also had two shots of speeders blowing up that were wire explosions. And I think we had one or two where we used another trick of losing the ship with some help from the animation department in the last few frames, just to sweeten the shot.
Photos: Edited footage from the lightsaber duel between Luke and Darth Vader was turned over to the ILM animation department where it was projected a frame at a time so that animators could airbrush cel overlays of the shimmering blades. The painstaking task was complicated by the fact that the actual swords used by the actors frequently disappeared in a blur when swung through the scene. The cels were later photographed on a custom animation stand and superimposed back in over the stage photography.
When you have shots which are just incredibly intricate and complex — like a number of the ones where the Millennium falcon is being chased through the asteroid belt — how do you go about first conceptualizing and then executing something like that?
It's a building process. One of the key shots in that sequence featured the Falcon wheeling its way through this field of flying rocks; and in order to pay off on the idea that they have a real rough row to hoe, we wanted to have one of the TIE ships that's following it crash into an asteroid. So there's a lot of activity going on, and each of the elements — including the separate pieces of rock — all needed to be shot individually, normally you start by programming out the most important compositional element in the shot first, which in this case happened to be the largest asteroid. So we shot that, and then we went to the Millennium Falcon swerving around it — knowing that at a later time the animation department would put a shadow across the surface of the rock to tie it all in together. Then came the TIEs. The TIE ships are all pretty much anonymous, but nevertheless they're there, so once we had the rock and the Falcon flying by it, we programmed and shot each of the TIEs separately. So we had the first TIE flying through, the second TIE flying through, and the third TIE flying through. But at this point in the composition we wanted the third TIE to collide with an asteroid, so we then programmed in the rock that the third TIE would collide with and flew it into the scene. As each individual element is programmed, we shoot a black-and-white test that we can process right on the spot to preview the move. Since it's negative film stock, the image is positioned against a clear background. Therefore we can multipack up to six or eight of these tests in a custom viewer and check all the elements at once to make sure everything's fitting together right. Assuming it is, we can then start filling in the composition. In this case, we added quite a few more rocks to make the asteroid field look really dense. Then, to make it even more precarious-looking, we had some of the rocks flying in one direction and some in another. Then there were three background paintings of more rocks that were filmed with a multiplane technique — and of course a star field. So by the time you've shot four ships, ten or twelve separate rock elements, three background paintings, a star field, plus miscellaneous explosions and shadows and lasers, you wind up with maybe twenty-five separately photographed pieces of film each of which has to be broken down into color separations and each of which has to have all the intermediate bluescreen steps to extract mattes. So all together, you have maybe a hundred and twenty pieces of film involved. And I'll tell you, the poor guy who runs the optical printer has really got to love his work, because he has to put it all together and make sure the color balance is just right and all the matte lines are gone. That particular shot had to be put together about four times to get it just perfect.
In Star Wars, George Lucas cut together a reel of World War II flying footage as a prototype for the final dogfight. Did you do anything comparable to this for some of your more complex sequences in The Empire Strikes Back?
As a matter of fact we did, but this time we used some rough animation instead of live-action — kind of like moving storyboards. When you're in a situation where you have literally hundreds of shots to deal with, it's extremely important that you get as much of the arbitrarity out of it as possible so you can actually understand what it is you're supposed to be doing. It's not enough to think of a shot in terms of ships flying through in one way or another. If you understand it only to that extent, you may end up with some very nice shots, but you're going to have a second-rate sequence. In order to make a first-rate effects sequence, you have to understand how the sequence flows, and how each shot interacts with the ones around it. In the case of George's much-heralded 16mm dogfight film, what he was trying to do was show what he had in mind in terms of dynamics — to show that when one pilot turned his head and his eyes darted to the right, then the next shot you cut in there ought to have a continuity of action. It wasn't just a matter of flying these ships through a shot here and there. Everything had to be integrated, and everything had to serve some kind of dramatic function. So anything you can do that will provide a point of departure for discussion, and provide some overall understanding of what's going on for the guys who are actually out there doing the work, is wonderful — even if it's just funky animation done with storyboards and a few cels. It gives you a frame of reference. But it was only an organizational tool. It's not as though we drew out the sequences and then shot them exactly that way — there was a lot of room for interpretation. Also, it's a great help in cutting the picture, because there's nothing worse than watching a picture and then suddenly there's a black slug in there that says "scene missing" — it completely disrupts your editorial train of thought. So with these animatics, at least you have something to put in there, even if it's just simple cartoons or World War II planes flying through a space movie — at least you still have the dynamics.
Photos: Effects cameraman Ken Ralston aligns a battle-damaged TIE fighter in preparation for a bluescreen matte shot. / Model maker Tom Rudduck examines a pair of cloud cars sent out to intercept the Millennium falcon as it nears the floating city of Bespin. / Special projects coordinator Stuart Ziff prepares for a shot featuring the Imperial star destroyer. The eight-foot vessel, mounted on a rotating model articulator, replaced the three-foot version used in Star Wars. / An exotic rebel cruiser provides sanctuary for Luke and Leia at the close of the film. / Matte painting supervisor Harrison Ellenshaw at work on a painted representation of bounty hunter Bob a Eett's ship, at rest on the Bespin landing platform. Ellenshaw — who had been previously committed to The Black hole — joined the ILM unit in the latter stages of the postproduction effects effort. In only six months, he supervised the preparation and photography of nearly fifty matte paintings.
Let me ask you something. Was there anything in the picture that you didn't buy because of the effects?
Not very much. There were a few shots in there where you could see through some of the ships.
Ah, you noticed those. I noticed a couple, too — to my dismay. That's a result of transparency in the mattes. If your matte is even a fourth of a stop too thin you're going to have that problem, and I guess a few of those slipped by. I don't mean to suggest that nobody noticed, but when you consider that we had something like 440 shots to do, it's not always possible to perfect every one of them a hundred percent — there just isn't time. We worked our way through the production schedule, and as we completed shots some of them would be perfect, others had to be redone, and others yet went onto a "could-be-better" list that included all the shots we could probably get by with if we had to. Then we developed priorities within that list, and as time permitted we'd rework them. Unfortunately, there just wasn't enough time to go back in and fix all of them.
Another thing — I thought the matte paintings used in the cloud city sequence were fairly obvious.
I think one of the problems you have with any "city of the future" idea is that your audience knows it has to be something like a matte painting or a miniature, because it couldn't possibly be anything else. If you do a matte painting of a castle on a hill, then most people are going to accept it because they know a lot of castles have indeed been built on hills. On the other hand, if you see this huge city shape perched on top of a golf tee hanging in the clouds, you know that it has to be some kind of a miniature or a painting. So right off the bat, you're starting out with a real heavy strike against you in terms of truly convincing anyone that it's there.
Frankly, I think that whole sequence would have been helped by having a very large, detailed miniature of the city, but we just didn't have time. As it was, we built at least fifty miniatures for this picture, including a lot of new spaceships. We had Darth Vader's executor star destroyer, the speeders, transports, and number of others. The ship that Luke and Leia are featured in at the end was an enormous project that was added late in the picture. And it was a fairly complex model that we had to set up so we could do projections into it and so on. So even though, in terms of motion pictures, we may be the closest thing to having what might appear to be NASA-type funding, we really don't. We're very frugal with our expenditures and we do our best to bring the picture in for a reasonable sum. And I think we did bring it in for a reasonable sum — especially in comparison to some other recent films where the effects work has cost astronomical amounts of money. So at any rate, we decided on a matte painting for the cloud city. Ralph McQuarrie did it and it's a very nice painting, but I'll agree with you — offering the above excuse — that the illusion is not quite perfect.
We have a lot of painting that work very nicely though, I think. My favorite is one on Yoda's planet where Luke's X-wing is in the bog and there's some smoke coming out of it and a couple of birds flying through the scene. Harrison Ellenshaw did that one, and it's all painting except for a little foreground water with
some fog. All we added was the smoke coming out of the X-wing, and the birds which were animated. There were some other good paintings as well — several in the area where Darth and Luke were fighting. Another one actually featured Joe Johnston, the art director for our effects facility, Ralph McQuarrie, Harrison Ellenshaw, and Mike Kelly of the editorial department. That was shot in the hangar when they're taking off. We dressed those guys up in costume and shot the matte painting behind them with bluescreen. Ralph did that particular painting, so it was kind of neat to have the guy who actually did the painting moving around in front of his own artwork.
What kind of a matting system did you use for your paintings?
We used a front projection system on Empire, although we're now building a rear projection system that I think will be the ultimate matte painting device since we'll be able to fly the matte camera using motion control. Anyway, with the front projection system, you do your paintings on glass and leave holes wherever the live-action elements need to go. Then you just put Scotchlite front-projection material directly behind the holes and project your action onto it through a front projection beamsplitter. It's a nice quick method for doing certain kinds of matte paintings.
On Star Wars, the lightsaber duel between Darth Vader and Obi wan Kenobi was shot on the stage using swords covered with that same kind of highly-reflective front projection material. The process wasn't totally successful, though, so you ended up having to enhance just about all of it with animation. Was the same system used on The Empire Strikes Back?
No, unfortunately. Since they figured it was going to be animated anyway, they didn't use the front-projection material this time. And it made it much more difficult for us, because last time — even though the effect was not totally satisfactory — at least we could always see the swords. This time, especially wherever we had a situation where they were being swung mightily through the scene, the image tended to disappear in a blur. So it was much more difficult to plot the animation.
You once rated the Star Wars effects as being 3.5 on a scale of 10. Mow would you rate The Empire Strikes Back?
Actually, I think it was George who was quoted as saying that — I just tended to agree with him. But if I had to rate Empire, I guess I'd have to say it broke fifty percent — maybe 6.5.
Do you think you'll make it up to 10 with Star Wars III?
No, I don't think so. One of my pet philosophies has to do with the necessity of remaining an amateur. The reason for that is my feeling that if you work real hard at something for ten years and finally decide to call yourself an expert, then the minute you do that you've locked yourself off. The idea of remaining an amateur is important, because if you are an amateur you can still be awed by something and your curiosity can still be piqued — whereas, if you're an expert, you tend to shore up your castle and sit in it. So I think the time I start thinking I'm approaching 10 on the scale is about the time I should start thinking about retirement.
Photos: Conceptual artist and design consultant Ralph McQuarrie was enlisted as a matte painter during the final months of the production, and personally executed about half of the paintings in the film. / Matte cameraman Neil Krepela shoots a McQuarrie painting of the sky city landing platform. Most of the paintings were done on glass with clear areas left open so that live-action elements could be front-projected into the scene on a separate pass. / In the final composite, only the underside of the Millennium Falcon and the landing platform and ramp surface area are real — everything else is painted.
[Source: Cinefex issue #2, August 1980. P4-23. Copyright © 1980 by Don Shay. The Empire Strikes Back photographs copyright © 1980 by Lucasfilm Ltd. All rights reserved. Special effects unit still photography by Terry Chostner and Howard Stein.]