To us at the Committee for Skeptical Inquiry, there was little mystery about the white objects seen in the sky over New York City on October 13. They were almost certainly party balloons of some kind. Why such confidence? Because there was a similar "UFO" sighting in Buffalo, New York, where we are located, in 2003 -- and our research team was able to duplicate original-witness footage by launching a few shiny mylar balloons into a clear sky.

In 2003 a local radio station sent us the video taken by two local witnesses. (We were then known as the Committee for the Scientific Investigation of Claims of the Paranormal, or CSICOP.) It showed three small white dots flying through the sky and moving relative to each other. It also showed the three dots flashing on and off, a phenomenon not reported by the New York City witnesses. More on that below.

After several experiments, we were able to determine that shiny silver Mylar party balloons best replicated the original footage. Once they'd climbed a few hundred feet they put on a captivating show, dancing about each other and drifting through the sky. The resemblance to the New York City phenomenon is so good, I for one am saying "case closed."

We posted three video clips. One documents the actual launch of our test balloons, so you can see just what was really in the sky. The latter two show how the balloons looked when shot by two different camcorders. Those clips show the "flashing" effect which we were setting out to duplicate because it appeared in the 2003 witness footage. That's not relevant to the 10/13 sightings in NYC, just concentrate on how the balloons look when they're clearly visible.

For curious readers: Why did the original 2003 footage flash? Close study of the 2003 tape revealed that the witnesses were not watching the sky, but rather their camcorder's LCD screen at the time the objects "flashed." So they didn't notice that the flashing occurred only in the camera, not in the sky. It was their camcorder's autofocus, racking back and forth because the three tiny dots in a cloudless sky weren't giving it enough detail to focus on. Again, this is not relevant to the NYC sightings, but it helps explain why our test tape from 2003 makes such a big deal about the flashing.

The concept: Having grown tired of the Navy SEALs, pro wrestling, and governing a state revered for its lutefisk, Jesse Ventura has created one of those ill-defined research institutes consisting mainly of a meeting room with cool lighting. Its goal: to finally get to the bottom of all those pesky conspiracy theories. Ventura has surrounded himself with young, geeky-looking "investigators" whose credentials aren't even hinted at. (One thing's for sure: acting is not among them.)

Come to think of it, neither is investigating. If the pilot episode is typical of what's to come, Conspiracy Theory will begin each episode by choosing an event or phenomenon worthy of conspiracy theorism (is that a word?), spinning out every ludicrous claim that any crackpot has ever connected with it, assume they're all true, and set out to prove it all. Sharp-eyed readers will note that I completed the preceding sentence without once using the word "investigating."

For the pilot episode, Ventura and his geek squad took on HAARP, the High Altitude Aurora Research Project in Alaska. This is a big antenna farm designed to pump powerful low-frequency radio signals into the ionosphere to stimulate unusual aurora which researchers can then study. A low-frequency radio installation that size (more than a billion watts of power) almost certainly lends itself to some military applications such as communication with submerged submarines. But beyond that...

Hey, this is Conspiracy Theory, and "beyond that" is exactly where Jesse and his Gang That Couldn't Think Straight will go. Apparently possessing an unlimited travel budget, squad members and camera crews fan out across the continent. One interview subject demonstrates an apparatus in which an electric arc in an enclosed tube causes vapor to rise. This of course proves that the real purpose for HAARP to beam a billion watts of radio energy skyward is to control the weather. Another interview, with the disaffected son of a deceased HAARP scientist, lays it all out. HAARP is good for shooting down missiles, controlling the weather, and messing with people's minds. Did you know that when coalition forces liberated Kuwait during the Gulf War, Iraqi soldiers surged out of their hiding places to surrender without firing a shot because HAARP had sent a signal halfway around the world to jangle their brains?

The interviews that support the show's agenda are ridiculous enough. Far richer in unintentional humor are the interviews that don't. One "investigator" tries to pry something incriminating out of two former HAARP scientists, hits a brick wall, and doesn't notice. Weather control? "Nope." Antimissile defense? "Nope." The segment ends with the voice-over narrator wondering why they won't tell what they really know. Finally, Ventura himself simply shows up at the gate of the scientific-military facility to be told that even though he's a former SEAL and a former governor, he still can't come in for a tour. The encounter ends when the videographer starts getting mysterious digital "hash" in his viewfinder. We are left to assume that HAARP's mad scientists diverted a few megawatts of their awesome evil power to tamper with the Conspiracy Theory crew's equipment.

Production values are state-of-the-art for this kind of show: much rapid cutting, repeated flashes of stock shots and effects shots that seem to "prove" the program's contentions. When it's over, the uncritical viewer will be scared to death of an innocuous scientific facility, and yet the producers will be able to deny most of the blame they deserve because their most ludicrous contentions were never actually proven onscreen, merely implied through leading narration and misleading cutting.

TruTV and this show's producers can be proud of themselves (they're obviously the sort who would take pride in such things). They've managed to take crappy pseudoscientific pseudo-reality TV to a whole new layer of sliminess. And don't miss next week's episode, in which Jesse and his gang will reveal what really happened on 9/11.

The events began on Thursday, June 20, with a press conference that drew a record media turnout. It was there that conference organizer Paul Kurtz, chair of CSICOP, Kendrick Frazier, editor of Skeptical Inquirer, and many others presented examples of the media’s pandering to pseudoscience. Kurtz announced the formation of CSICOP’s Council for Media Integrity, a new watchdog group that will monitor and respond to media mishandling of the paranormal. “The media have now virtually replaced the schools, colleges, and universities as the main source of information for the general public,” said Kurtz, according to press reports. “If you look at these shows, Unsolved Mysteries, Sightings — there are a whole slew of them — they make it seem as if what they're portraying is real. Yet they don’t provide any scientific evidence.” Kurtz called for either allowing a fair chance for the rebuttal of questionable material or presenting it as fiction.

CSICOP fellow Joe Nickell also made comments that were picked up by the media. With respect to claims of UFO abductions, he was quoted by Ulysses Torassa of the Religious News Service as saying, “I'm now encountering children who believe that they might be abducted by extraterrestrials.” Also quoted by Torassa was Australian skeptic and TV moderator Phillip Adams, who pointed out, "We are seeing a new delivery system for pathological states of mind.”

The congress itself opened formally with remarks by Erie County (New York) Executive Dennis Gorski and a performance of selected movements from Gustav Holst’s The Planets by the Buffalo Philharmonic Ensemble. This performance was accompanied by a special video production based on NASA images of the planets, for which the suite’s movements are named, refocusing The Planets from the composer’s original astrological conception of the work.

Milton Rosenberg, Professor of Psychology at the University of Chicago and longtime radio moderator, chaired the meeting’s first plenary session, “The Role of the Mass Media in (Mis)Informing the Public.” Panelists included George Gerbner, Professor of Communications at the University of Pennsylvania; Piero Angela, Italian TV journalist; Phillip Adams, Australian columnist and TV moderator; and John Allen Paulos, Temple University Professor of Mathematics and author of Innumeracy. Nationally known radio commentator on medical subjects Dr. Dean Edell also participated by live radio feed as part of his syndicated radio show which airs on several hundred stations. In what was perhaps the congress’s only misstep, one of the panelists onstage mistook Edell’s scheduled participation as an interruption in the program and criticized Edell for disturbing the proceedings. The error was redressed minutes later when Paul Kurtz appeared on Edell’s program by telephone for about six minutes clarifying what had happened and outlining CSICOP’s call for heightened media responsibility, a call which Edell himself has long advocated.

The Conference Address, “A Strategy for Saving Science,” was delivered Thursday evening by Leon Lederman, Nobel laureate in physics and Director Emeritus of Fermilab.

The congress resumed Friday with a plenary session entitled “The Growth of Anti-Science,” chaired by John Maddox, former editor of Nature. The participants included Paul R. Gross, director of the Center for Advanced Studies; Norman Levitt, Professor of Mathematics at Rutgers University; Susan Haack, Professor of Philosophy at the University of Miami; and Victor Stenger, Professor of Physics at the University of Hawaii.

Skeptical Inquirer editor Ken Frazier and X-Files creator Chris Carter.

A luncheon address was given by Chris Carter, creator of the Fox TV series The X-Files. Carter defended his series against critics who say he promotes paranormal beliefs. He claimed that the series is meant solely to entertain and should actually heighten, rather than dull, viewers’ skepticism. But at least some congress participants doubted such an optimistic assessment of the program’s effects.

The afternoon was devoted to concurrent sessions. One session was on UFOlogy, given by Philip J. Klass, James McGaha, and Robert Sheaffer. Another program dealing with astrology was given by Cornelis de Jager, J.W. Nienhuys, and Ivan Kelly, while homeopathy was considered by Wim Betz and James “The Amazing” Randi. Vern Bullough, Bela Scheiber, and Dale Beyerstein examined therapeutic touch. Prominent anti-health-fraud activist and author Dr. Stephen Barrett discussed chiropractic. And National Center for Science Education Executive Director Eugenie Scott and Professor of Anthropology H. James Birx looked at the evolution/creationism controversy.

The Keynote Address was given by Harvard University paleontologist Stephen Jay Gould, who drew (according to one local media estimate) some two thousand persons to an illustrated lecture on Darwin, evolutionary theory, and the role of skepticism in forming and evaluating hypotheses.

Saturday opened with a plenary session titled “Parapsychology: Recent Developments.” This session was chaired by James Alcock, Professor of Psychology at York University in Canada, and featured: Ray Hyman, University of Oregon Professor of Psychology; Richard Wiseman, University of Hertfordshire (U.K.) Professor of Psychology; Jessica Utts, University of California-Davis Professor of Statistics; and Stanley Jeffers, York University Professor of Physics and Astronomy. The focal point of this session was the disagreement over interpretation of laboratory studies of parapsychology by Hyman and Utts, who had come to contradictory conclusions after analyzing data from the U.S. government’s Stargate project. Utts believes that meta-analysis has clearly proven the existence of some sort of cognitive anomaly such as psi, so that further research should be aimed at probing its nature rather than multiplying efforts to establish its existence. Hyman believes that the existing studies are generally so flawed that they do not constitute proof of any anomaly, so that the existence of psi remains a very open question and one clouded by more than a century of laboratory failures to isolate a replicable psychic phenomenon.

John Maddox, emeritus editor of Nature, spoke on the importance of the scientific method at a gala luncheon at The Center for Inquiry, located across the street from the State University of New York at Buffalo’s Amherst Campus.

Saturday’s concurrent sessions included “Mechanisms of Self-Deception” by Barry Beyerstein, Thomas Gilovich, and John Schumaker; “Alternative Health Cures” with Jack Raso and Wallace Sampson; “Philosophy and Pseudoscience” with Paul Kurtz, Daisie M. Radner, Lewis Vaughn, Theodore Schick, and Tim Trachet; "Psychoanalytic Therapy and Theory After 100 Years” with Adolf Grunbaum; "Critical Thinking in Education” with John Kearns, Clyde Herreid, Lee Nisbet, Carol Tavris, and John Corcoran; “Spiritualism and the University at Buffalo Expose” with Joe Nickell and Gordon Stein; and “The Paranormal in China” with Chinese skeptics Madame Shen Zhenyu, Lin Zixin, Sima Nan, Zu Shu-Xian, and Guo Zhenyi.

The last two of the above-mentioned sessions were of special interest. For as it happens the University of Buffalo (UB), a precursor of SUNY at Buffalo, was celebrating its 150th anniversary during the congress, and one of the first "extracurricular” activities undertaken by UB faculty a century and a half ago was one of the earliest scientific examinations of the Fox Sisters, three young women whose floor-tapping activities launched nineteenth-century spiritualism. The UB investigators succeeded in partially unmasking the Fox Sisters’ fakery, an expose which was, tragically, insufficiently noted at the time. In later life, the sisters themselves confessed to having been frauds.

The session on paranormalism in China, meanwhile, represents the latest fruit of a long and productive relationship between CSICOP and pro-scientific persons and organizations inside mainland China. The session also included a report by members of the CSICOP delegation to China, which recently returned from an expedition of fact-finding and investigation of Chinese paranormal claims.

Stephen Jay Gould accepts the CSICOP “Isaac Asimov Award” from new CSICOP Executive Council Member Eugenie Scott.

Leon Lederman accepts the CSICOP “In Praise of Reason Award” from astronomer Cornelis de Jager.

An awards banquet followed Saturday’s sessions at the Hyatt Regency Hotel in downtown Buffalo. CSICOP bestowed the Isaac Asimov Award upon Stephen Jay Gould. The In Praise of Reason Award was presented to Leon Lederman; the Public Education in Science Award to Dr. Dean Edell, who accepted via videotape; and the Distinguished Skeptic Award to James “The Amazing” Randi. The Distinguished Skeptic/Lifetime Achievement Award was given to talk-show host, humorist, author, and general Renaissance man Steve Allen, and the Responsibility in Journalism Award went to Phillip Adams, Piero Angela, and Pierre Berton. The banquet was also marked by news that independent astronomical working groups had succeeded in naming asteroids for Paul Kurtz and CSICOP. The CSICOP asteroid ended up being named “Skepticus” after concerns were aired among astronomers that people might not know how to say “Csicop.” Steve Allen, author, entertainer, and creator of the original Tonight Show, provided entertainment at the banquet.

Sunday’s session was devoted to a three-hour “World Skeptics Update” in which leaders of skeptical groups from across the globe described the situations in their home countries. Participants included Tim Trachet (Belgium), Mario Mendez Acosta (Mexico), Amardeo Sarma (Germany), Michael Hutchinson (UK), Miguel Angel Sabadel (Spain), Henry Gordon (Canada), Stephen Basser (Australia), Lin Zixin (China), Massimo Polidoro (Italy), Cornelis de Jager (Netherlands), Valery Kuvakin (Russia), Rudolf Czelnai (Hungary), Premanand (India), and Sanal Edamaruku (India).

The congress attracted unprecedented media coverage, including partial coverage on C-Span. In addition, National Public Radio’s “Talk of the Nation: Science Friday” program made a rare trip out of the studio to originate from the congress site with host Ira Flatow. The congress was also distinguished by the raising of more than $200,000 toward the “Fund for the Future” campaign, a $20 million Center for Inquiry program and endowment fund. Congress proceedings are now available on audiotape.

Figure 1. The start of a dolly forward-zoom back shot. Camera with telephoto lens films two persons standing side by side. A telephoto lens captures an image along a narrow angle, so in order to fit both actors into the frame the camera must be placed a moderate distance away. Even so, because the narrow angle the image subtends a narrow slice of the background behind the actors.

Figure 2. The end of the shot. The lens has zoomed from telephoto (narrow angle) to wide angle. Because of the wide angle the camera must move closer to the actors to keep their images filling the frame. But look at the background! In spite of the camera’s forward movement, the image subtends a much broader portion of the background.

Photos A, B, and C illustrate the same process.

Photo A. CSICOP Senior Research Fellow Joe Nickell stands in profile, pointing. His image fills the frame. This image was made with a telephoto lens (135mm lens on 35mm camera) from a substantial distance away. Note how little background is included, which is why Skeptical Briefs production editor Tom Genoni (out of focus in the background) subtends about a quarter of Joe’s apparent height.

Photo B. Made with a 50mm ("normal”) lens. I moved substantially closer to keep Joe the same relative size in the frame. We see a lot more background; Tom has shrunk appreciably.

Photo C. Made with a 24mm (wide angle) lens. I’m only a few feet from Joe, and the entire Center for Inquiry stands tiny in the background. Tom is almost invisible.

Imagine a motion picture sequence that moved through this range. The apparent separation between Joe and background objects would increase dramatically. The emotional subtext would suggest Joe being wrenched from his surroundings, or perhaps his environment fleeing from him. Powerful stuff.

Photos D, E, and F show what happens when one zooms in while keeping the background roughly the same size.

Photo D. Shot with telephoto lens from about 75’ away. Library windows fill the image from side to side. CSICOP staffers Marsha Carlin and Etienne C. R'os seem to occupy the same plane though Marsha stands about 12’ in front of Etienne. (See where their feet are!)

Photo E. Shot with a normal lens. Marsha and Etienne have not moved, yet their apparent separation has ballooned.

Photo F. Shot with wide angle lens. I’m only about 2’ from Marsha, too close to hold her in focus! She and Etienne seem to be in different zip codes. Both also seem much more distant from the building.

Last issue, we examined the once-difficult, now-routine motion picture shot in which the camera dollies forward while zooming out at a rate which maintains the foreground subject at a constant size. The eerie result: While the foreground character remains stationary, the background flees outward in all directions. It’s a great way to express sudden isolation or dramatize a character’s response to some shocking revelation. No sooner did I finish writing the last installment than I saw Ron Howard’s Apollo 13. That film uses the dolly forward-zoom out technique for a brief reaction shot of flight director Gene Kranz (Ed Harris) at the moment when the astronauts report their emergency. It’s sound movie-making — and one more indication that this formerly-exotic device has become an accepted part of film grammar.

But what makes it work? Consider the effect of lens length and camera-to-subject distance — in a word, of perspective — on the way a shot “feels.”

By selecting lens length and camera distance wisely, movie and TV directors can control the emotional resonance of their shots — creating subtle impressions of camaraderie or loneliness, enmeshing individuals in their environment, thrusting them into savage isolation, or placing a romantic couple in a “zone of their own” set off from their surroundings. It’s one of the strongest ways to influence audience response to an image, yet few suspect anything — until a director draws attention to the process by means of a bracing dolly in-zoom out shot.

Effects technology has made countless strides since Star Wars launched the revolution in 1977. Still, one of the major reasons fanciful creatures and objects look better in today’s productions is that effects artists have largely solved the problem of injecting suitable blur into their work. In this column, we'll see how.

For Star Wars, effects supervisor John Dykstra developed the first practical motion-control camera system for dynamic photography of spaceship models. Highly repeatable stepper motors drove a camera boom that swept over almost-stationary models. Multiple passes of the same shot could be made in perfect alignment: one to capture the model itself, one for its on-board lighting, one to obtain a perfect silhouette for later use in “matting” the model into a background image, and so on. With early motion- control systems, a two-second model ship fly-by might take hours to shoot. Camera speed was slowed down proportionately; for each frame, the shutter might open for several minutes while the camera crept past the model. During each frame the camera moved approximately as far relative to the model as it would have in a “real” shot. Near-perfect blur was automatic. The result was a more realistic impression of fast and violent motion than had ever been achieved before on the screen. In Spielberg’s Close Encounters of the Third Kind (1977), effects designer Douglas Trumbull used similar technology to produce realistically-blurred multipass images of glowing UFOs.

By the time Spielberg made his ill-advised John Belushi comedy 1941 (1979), technicians at Industrial Light and Magic (the Marin County, California, effects factory that grew out of Star Wars) were experimenting with a technique called “go-motion.” As the name implies, go-motion was a direct attempt to address the blur problems inherent in stop-motion photography of miniatures. Additional computer-controlled stepper motors were attached not to the motion control camera boom, but to the miniatures themselves. Instead of being posed by animators between frames and photographed at rest, go-motion miniatures would move, repeatably, at microscopic speed. In 1941 go-motion contributed to a few long shots of a Japanese submarine on the surface. Spielberg wanted to do camera moves over the sub and matte it into background imagery of the Pacific Ocean even though crewmen were visible on the sub’s deck. This would have created an insuperable compositing challenge if go-motion had not made the little crewmen on the model sub move exactly the same way in pass after pass.

Go-motion came into its own in Spielberg’s E.T., the Extra-Terrestrial (1982). Remember that film’s signature image: E.T. and his young human friend crossing before the moon on a flying bicycle? Go-motion motors repeatably rotated the bike’s spoked wheels, making possible complex composite shots where the smooth, realistic wheel movements “sold” the effect.

When ILM tackled Return of the Jedi (1983), the finale of the original Star Wars trilogy, go-motion technology wasn’t ready for the challenges it posed. (Jedi featured scores of composite shots with bright backgrounds: forests, deserts, smoky rooms with lots of backlight-far harder to composite than shots with dark outer-space or night-sky backgrounds.) To produce the Rancor, a fifteen-foot lizardlike biped that menaced Luke Skywalker in Jabba the Hutt’s lair, effects supervisor Dennis Muren rejected both stop-motion and go-motion. Instead, animators Phil Tippett and Tom St. Amand used puppetry and concealed rods and wires to manipulate the miniature Rancor, which was shot “live”-that is, actually moving-with slow-motion photography.

James Cameron’s The Terminator (1984) was the last major film to offer an old-fashioned, jerky stop-motion character. The Terminator robot (supposedly Arnold Schwarzenegger’s endoskeleton) was realized with life- sized puppets wherever possible. For certain long shots, there was no way to avoid stop-motion (and no money for go-motion). Animator Peter Kleinow used a Vaseline-smeared glass plate between the lens and the model to suggest blur, but it didn’t work.

Back on the high-tech front, The Golden Child (1986) gave ILM a chance to try out a new real-time motion control recorder. For a sequence of Eddie Murphy battling a man-sized demon, director Michael Ritchie shot live-action footage of Murphy fighting a non-existent opponent. The camera moved freely; in some shots it was hand-held. Effects technicians used field recordings of all that movement to apply precisely matching moves to their go-motion footage of a miniature demon. The shots were amazingly good, especially considering that Ritchie jerked his live camera more enthusiastically than the ILM gang originally had in mind.

Robocop (1987) showed that a gifted animator could get good results even with plain old stop-motion. Shots of the ED-209 “enforcement droid” were done stop-motion in front of rear-projected backgrounds-just the way Ray Harryhausen did films like Jason and the Argonauts (1963), whose failings I discussed in my previous column. Tippett, by then Hollywood’s master stop-motion artist, added convincing blur in a refreshingly low-tech way. While exposing each frame, “we introduced blurs basically just by wiggling the puppets,” he told Cinefex. It was the last sustained used of stop- motion in a major Hollywood picture, and it worked remarkably well.

When Spielberg started planning Jurassic Park (1993), effects artists planned to execute long shots of the T-rex, velociraptor, and other dinosaurs using go-motion miniatures. Advances in computer graphic (CG) animation persuaded the makers to abandon go-motion in midstream. A huge ILM crew under supervisor Dennis Muren realized the full-body dinosaurs as perfectly- realized three-dimensional computer constructs. (Continuing the vocabulary of “stop-motion” and “go-motion,” they called the new method “full- motion.”)

Mathematically-exact blurs were incorporated right into the images as the computers rendered them; as every living human knows, the results were perfect. Phil Tippett had been hired to direct the go-motion work; instead he shared with the CG artists his deep understanding of how to make artificial creatures “perform,” and helped develop a number of “waldoes” (wearable hand or body rigs that let animators feed motions to their computers in a more lifelike way than by typing start points and end points into a computer console).

Another ILM crew under supervisor Mark Dipp used Jurassic Park technology to create more fanciful CG dinosaurs for The Flintstones (1994). One “must-have” scene replicated the familiar cartoon gag in which Dino, Fred Flintstone’s purple pet dinosaur, drags Barney (Rick Moranis) across Fred’s living room at the end of his leash. The background shot was a blurry pan shot that followed Barney across the soundstage living-room set. For the computer, applying proper blur to Dino’s movement plus matching the blurs introduced by the background camera’s movement was a piece of cake; stills from this sequence are amazing in the realism and correctness of the blur they displayed.

Where do we go next? High-end CG imagery is migrating onto simpler and less costly computers. Instead of the high-end Silicon Graphics workstations used in Jurassic Park and The Flintstones, several shots of the Enterprise-D starship in Star Trek: Generations (1995) were created entirely as 3-D CG constructs. They were rendered, blur and all, on ordinary Apple Power Macintoshes using off-the-shelf software by ElectricImage, Inc. Rendering at motion-picture resolution took an average of just six minutes per frame.

Next time you go to the movies, don’t expect jerky, failed stop-motion shots to tell you how the shots were done. Hollywood’s effects artisans have long understood that convincing motion requires not only changes of position in successive frames, but appropriate blur as well. And the problems of creating it have been conclusively solved. Heck, by the time this column sees print you may be able to do it on your own desktop.

Effects pioneer Willis O'Brien made the giant-creature shots in King Kong using a technique called stop-motion animation. Stop-motion animators pose flexible model creatures (apes, dinosaurs, what have you) in miniature settings and expose a single frame of film. Then they move the creatures into the positions they would have assumed 1/24-second later if actually in motion, expose another frame, and begin the dreary round again. It’s laborious, but for decades it was the only way to bring truly outrageous objects “to life” in the cinema.

The thing to remember about traditional stop-motion is that none of the “moving” subjects are actually in motion when they are photographed. But an illusion of motion arises when the human eye views these still pictures, twenty-four of them each second, on a motion picture screen. (The numbers differ for video, but the same principles apply.)

Stop-motion is far from perfect. To see why, we must consider how motion picture images are created—and how the brain interprets them to produce the illusion of motion. A motion picture camera operating at sound speed exposes twenty-four frames per second (FPS). It’s a purely mechanical process— advance the film a frame, stop it, open the shutter, close the shutter, advance to the next frame—so less than half of the time between frames is available for exposing the film. The actual exposure time for a frame of motion picture film is about 1/60- second. If you've used a 35mm still camera that lets you set your own shutter speeds, you know 1/60-second isn’t very fast. If you photographed a basketball game at that shutter speed, you'd get blurry images of the players. To get stills that freeze the action, you'd want a faster shutter speed — say, 1/500-second.

Why do moving objects blur with exposures in the 1/60- second range? Imagine photographing a passing car. At 60 mph, the car moves 88 feet per second, almost a foot and a half during the 1/60-second that your shutter is open. How will the car look when the prints come back? It will blur, of course, reflecting the fact that the car was not in the same place throughout the exposure. Blur severity varies not with an object’s absolute speed, but with how much of the image area it crosses during an exposure. Set your shutter at 1/60-second, stand 200 feet from a superhighway, and snap a picture. The cars will only blur a little. Stand on the shoulder and snap that same traffic, and you won’t be able to tell Fords from Toyotas.

When it comes to blur, Hollywood movie cameras work just like your still camera at 1/60-second. They just cost more. Pop your favorite movie in the VCR. Freeze a single frame of an action scene. You'll see blurring you never imagined was there. But your brain notices it. More, it expects moving objects to be blurry.

That brings us to the question of how the brain interprets the projected motion picture image. Everyone knows the basic principle: Successive still images are flashed on a screen, and a phenomenon called “persistence of vision” keeps us from seeing the intervals of darkness between frames. We view the succession of stills as a continuous image. When an object changes position from frame to frame, we perceive that the object is in motion. But this isn’t the only cue that can fool the visual system into perceiving movement. 3-D movies exploited stereoscopic vision to create vivid impressions of movement. Conventional movies don’t take advantage of stereopsis. But they do take advantage of other assumptions the brain seems to make about moving objects. One such assumption is that the image of a fast-moving object will be degraded as a consequence of its movement. In other words, if an object is moving quickly enough across the visual field, the brain expects it to blur.

Keeping that in mind, we can reconstruct why the pilot’s- eye view shot in King Kong looked so good, and why the smash- the-airplane shot looked so bad. Since subjects in classical stop- motion do not move during exposures, they do not blur. For the pilot’s-eye view shot, Willis O'Brien rigged a stop-motion camera to roll down a track over a huge New York skyline diorama toward a model Empire State Building. Though the camera seemed to move at 150 mph, since the objects in motion relative to the camera (the skyline) were distant, nothing moved very far across the image area between any two frames. If the shot had been staged for real, you wouldn’t expect much blur. So the fact that the stop-motion sequence had no blur did not detract from the illusion of motion it created.

The smash-the-airplane shot was a fairly close, static shot. The airplane sped across the screen; Kong’s arm lashed out and struck it. With each frame, they crossed large fractions of the image area—normally a recipe for severe blurring. But stop- motion can’t blur! When viewing this scene, we experience conflict between two modes of visual interpretation. Objects change positions drastically from frame to frame, which tells the brain that they are moving quickly. But the absence of blur tells the brain that everything is stationary. Result: interpretive conflict. The illusion of motion is compromised.

Stop-motion shots that don’t have the blurring they need give viewers a “strobing” sensation. Objects jerk-jerk-jerk like dancers under an old disco strobe light. Three famous scenes created by stop-motion master Ray Harryhausen in the 1950s and 1960s exemplify the problem. Next time you find Jason and the Argonauts on late-night cable, watch how the swordfighting skeletons “strobe,” especially in close shots. Check out the jerky movements of the giant crab in The Mysterious Island. In One Million Years B.C., a stop-motion pterodactyl carries off Raquel Welch. Its wings flap in and out of frame at high speed—but with no blur. Even to untrained eyes, it looks profoundly wrong.

In the next installment, we'll see how moviemakers since the time of Star Wars have applied high technology—and sometimes, startlingly low technology—to inject blur into animated footage. Understanding how and why Hollywood professionals use blur to make their illusions more effective can help us all understand the myriad ways the eye can be fooled.

What’s going on here? We're catching our eyes in the act of second-guessing the color of everything we see. Even skeptics tend to think of vision as a simple, linear process. Researchers probing the details of vision say otherwise. Francis Crick, codiscoverer of the structure of DNA and a CSICOP fellow, devoted a book to summarizing vision research and its implications for understanding human consciousness (The Astonishing Hypothesis, Scribner’s, 1994). Visual experience is profoundly synthetic. Raw data from the retinas undergo extensive processing and interpretation, starting in the retina itself. Structures throughout the brain join in shaping what we seem to see so naturally through our eyes. But seeing is not believing.

The red-squares illusion illustrates the Land effect (discovered by Edwin Land, who went on to invent Polaroid photography). Here’s the problem: We never see the “actual colors” of objects. All we get to work with are the wavelengths of light they reflect. that reflected light can be affected by the object’s actual color or by the color of the light under which we view it. Or both. White paper under red light looks red. Red paper under white light looks red too. Yet we can usually tell them apart. How?

Apparently, still further up the visual-processing ladder, color information from one part of the visual field (the paper) is compared with that from the background. The brain tries to subtract the effect of colored illumination to restore the “actual” color of objects. That is the Land effect, and it’s why a white jacket still looks white instead of orange under the setting sun. Like most of the brain’s subterfuges, the Land effect can be fooled. Viewing those two red squares on different-colored backgrounds tricks the brain into thinking that the red square on the blue background actually lies under blue light. So it “compensates” by changing the square’s perceived color.

What’s remarkable is not that the brain’s color compensating apparatus can be fooled, but how well it usually works. We live our lives under many different colors of “white light” and hardly ever notice. Ever take snapshots indoors without flash? The photos come out with a strong orange cast. Were you about to say an “unnatural” orange cast? Bite your tongue! That ruddy tint is altogether natural. The light from a household table lamp really is that much redder than sunlight.

Professional photographers measure the color of “white” light in degrees Kelvin (degrees Celsius above absolute zero). “Color temperature” corresponds to the color of light that would be radiated by an ideal black body heated to that temperature. Lower temperature means redder; higher temperature means bluer. As shown in Figure 1, household incandescent lighting has a relatively low color temperature-about 3,000° K. (Only open flames-candles, campfires-are lower.) By contrast, direct sunlight has a color temperature of about 5,400° K., much bluer.Photographic film can’t compensate for the color of ambient light like as your brain does. Your film reproduces color most accurately at 5,400° K, the color of direct sunshine (and photoflash units). Your available-light indoor photo is taken at 3,000° K. You don’t see the color difference, but your film does. Result: orange snapshots.

Real life is a symphony of color temperatures most of us never see (Figure 1 again). Incandescents used in television and movie studios are bluer than household lighting, about 3,400° K. (Professional motion-picture films are balanced for this light; in low-budget movies, the view from the livingroom window often has a blue cast. Producers with more money put orange gels over the windows.) Open shade is about 400° K bluer than sunlight. Some of the high-intensity lights now used in Hollywood hit 6,200° K. They require orange gels to match sunlight! Outdoors at night, these units are often used without gels for maximum light output. That’s one reason that artificially lighted night exteriors in movies like Terminator 2 look so blue.

Since the 1970s, Hollywood has delighted in teasing us with the colors of white. Letting the colors shift suggests gritty realism: Remember the orange interiors of the Godfather films? Consider the way police station interiors are often lighted in cop movies. Most of the light looks white (3,400° K). The windows go blue (5400° K). And the little fluorescent lamps on everybody’s desk look green. Green? Color temperature isn’t the only variable in “white” light. Most fluorescents have a green spike in their color spectrum: They emit a disproportionate share of their light at green wavelengths. Untrained humans never see that extra green, but film does.

Why don’t home videos show the colors of white so strongly? Camcorders compensate for the color of ambient light much as the brain does. As for professional videographers, they point their lenses at a white card and push a "white balance” button. It’s their way of telling the camera, “Hey dummy, this is white.” The camera then adjusts its red, green, and blue gain until the card reads truly white, compensating for color temperature and color spectrum in one operation.

What are the lessons of all this? First, if you shoot snapshots indoors without flash, stop waiting for the magic day when your pictures will stop coming out orange. They never will. Second, the next time you’re tempted to accept the evidence of “your own eyes” without additional corroboration, remember about the color of white. It isn’t just your eyes that see, it’s your brain — and some of the tricks your brain performs to “improve” your visual experience can distort it as well.