On Empire, just as on Star Wars, we have used lenses with tilting mounts for shooting our miniatures. That was the first thing I decided we needed on the camera. It harks back to my days as a still photographer. I started out with a view camera and soon learned the advantages of being able to tilt the lens to achieve more depth of field than was normally possible when the lens was parallel to the film plane. If you are photographing (as you are in most cases) an object which is tilted toward the lens, such as a landscape going out before you, and you see the foreground three feet away and it goes back to infinity, and there are just clouds or a bald sky, you can achieve focus from two inches to infinity by tilting the lens forward. The cardinal sin in miniature photography is to have something soft in the foreground; that immediately brands it as a miniature, so you must have extreme control over your focus.
This is by no means the first time that motion picture lenses in tilting mounts have been used. Actually, the late Hal Mohr, ASC, had a ball-joint 50mm lens in his goodie box, which he would drag out and astound people with occasionally when the need arose, so I'm really just carrying on the tradition. A tilting lens board, to me, is an absolutely necessary part of miniature photographic equipment. We have several focal lengths available with tilting mounts.
We chose Nikon lenses for our special effects work because they have the best range of optics for the SLR cameras. The fact that there are so many SLR lenses available is another good reason why VistaVision (or an 8-perf, pulled-across film format) is the best effects format. We have a range of lenses from a 13mm rectilinear wide-angle lens to a 1000mm mirror lens and all of the units in between. All of the focal lengths have one flange distance; they all have the same filtering size. They are all of the same color, so they intercut well. One doesn't tend to be yellow and another one blue, causing that sort of problem. They are all very close to being the same in terms of the look they produce. By that I mean that one isn't crisper than the other one. There are, of course, certain lenses that are the sharpest and that we use for specific purposes, but from the wide-angles to the longer lenses they are all about the same quality, which is an advantage. Another plus is that we are able to buy these lenses for a few hundred dollars each. We'd have to think a little bit harder about using VistaVision were it not for the range of lenses available in that format.
I'd like to go into a bit more detail about the cameras we built for The Empire Strikes Back. We decided that if we were going to go ahead and design a camera, several could be built. As I mentioned previously, we've built two at the present time. One of them has a range from sound speed to unlimited time exposure. the other one presently goes from 96 fps to one second, but at some point this camera will be capable of going from 96 fps to long time exposures, as well.
We decided to build a VistaVision reflex camera because a reflex camera is generally the most pleasant to use, the most versatile and you can see what you are shooting as you shoot it. You can also add video viewfinders to relay the exact image that you are photographing.
It's very tricky to design a mirror reflex system and get it to a point where the image is steady, but, nevertheless, we decided to do that and we have done it. The camera is small. It uses Arriflex magazines, which is the only sane way to build a special-purpose camera, since part of the camera is already built into the magazine. You only have to drive your magazine and you have the loop formed for you automatically.
The magazine load is rather small—only 400 feet, but still an improvement over the 200-foot load used in standard 35mm photography. At any rate, since these are Arriflex magazines, they can be changed rather quickly. Since our cameras were designed specifically as effects cameras, we were not interested in putting 2,000-foot magazines on them for production use.
Our camera design includes a bloop light which sends a pulse to the recorder if you need to record sound. It has a ground glass viewing device which permits you to put a film clip in the finder on pins that are registered to and lined up with the register pins in the camera. This makes it possible for you to look through the clip and compose a matte shot in relation to a miniature previously shot, or vice versa. You can line it up exactly and see the perspective of the other shot in the finder. You can match forced perspective shots and things of that nature. As far as I know, this is the only reflex camera that has that capability. There are rackover cameras that have it and it's now a new idea. What we have designed is just a new implementation of an old idea. Much of our new effects technology has evolved that way, based on tricks that go all the way back to the original King Kong.
The camera has a reflex butterfly-type mirror shutter, which is similar to that used in most reflex cameras. The shutter is traditional in that it is one-to-one to the movement, which means that there is no chance of one frame getting a slightly less amount of exposure than the other frame. Such a problem would be much more pronounced in our work, since we have to deal with the image in duplication so many times. We have one shot in The Empire Strikes Back that has 20 separately photographed blue screen shots, each of which was put in as a separate item, and we managed to achieve matte density without matte lines of sufficient amount so that the scene didn't start to get milky after putting that many elements in.
Eastman Kodak has been very generous and very helpful to us on this production. We asked them to make 5247 on an Estar base for us and they agreed to do so. As a result, we shot all of our special effects on Estar base film, including the high-speed work and all of the separations, mattes and other elements. There were five different emulsions that we received on Estar base, 5247 being the first. The separation stock, 5235 had been supplied previously; 5369 had been supplied to the microfilm industry previously. I don't know about 5302, which we use for mattes sometimes. However, this was the first time they'd ever put 5247 on Estar. The live photography was not shot on Estar base, but the matte shots were wherever possible and this gave us a somewhat better dimensional stability than we were able to get on acetate base. Not that there is anything wrong with acetate base; it's just that because our parameters are so stringent and we deal with so many elements, there are many factors that play in our favor with Estar base. Even our daily prints came back on Estar, which meant that they didn't get chewed up in the projectors. Such accidents, which are common with acetate prints, would have killed us timewise, because we would have been forced to wait for reprints. The toughness of the Estar base 5247 was important to use, but our main reason for using it is its dimensional stability.
