Even Philip J. Klass, the field's number one skeptic, will admit to that. One huge selling point for Klass is that videos are so much more difficult to hoax than still photos. The usual tricks of photography, like double exposures and negative sandwiches, can't be done on video, though given enough skill, money, luck, and patience just about anything else can be done on video these days. Still, video has a kind of built-in honesty meter. The creation of a fake image must be accompanied by a fake soundtrack. Cries of "Hold that fishing pole steady" would be a dead give-away.

This illustration depicts an alleged UFO over Mexico City. The video evidence for an actual UFO, it turns out, merely captured the glowing visage of Venus.

That's not to say that videos are the perfect form of evidence. The picture quality, or resolution, and color of video is inferior to still photographs, but videos do provide a record of an object's motion and speed. Perhaps the best thing about videos is that they are essentially free, meaning that people will shoot nearly anything — and they do. And unlike still photography, videos lack the "shame factor." You don't have to hand your film over to some clerk who is going to smirk at you and say, "Gee, what's this? Have you had aliens visiting you?"

Home videos are actually good enough to serve in scientific investigations. In fact, a precedent has already been set for using amateur videos in scientific analysis. When a meteor streaked over West Virginia on the night of Oct. 9, 1992 and 40 seconds later crashed into a parked car in Peekskill, New York, 14 videotapes were taken of the object's trajectory. Using these tapes, scientists calculated the meteor's path, its ablation characteristics, orbit, etc., and published their findings in the Feb. 17, 1994 issue of the prestigious scientific journal, Nature.

Actually, one notable UFO episode has already been caught on tape by more than a dozen videographers. During the total solar eclipse of July 11, 1991 at least 18 videos were taken of a small, bright, silvery object which hung motionless in the sky over Mexico City and nearby Puebla. Mexican TV journalist Jaime Maussan called it "the most important collection of videotapes ever assembled in history." But UFO investigator and journalist Antonio Huneeus discovered otherwise. "It was the Queen of the IFOs," says Huneeus. "Venus was precisely at that spot in the sky where the video cameras had taped the so-called UFO during the eclipse."

Even if someone were lucky enough to spot a true UFO, getting a good video is no easy feat. A lot more information could be extracted from UFO videos, notes Sainio, if people would follow a few simple rules. First, use "SP," the slowest tape speed. Second, get reference points — like trees, telephone poles, buildings, and other aircraft, if possible — in the same shot as the UFO. Third, describe what you see as you are taping, as well as the time, wind, temperature, etc. It would also be extremely helpful, says Sainio, if people provided complete documentation with their video tapes, in other words, the camera type, direction in which it was pointed, etc.

But Sainio is not hopeful that such instruction will bear fruit. "The problem is that people who are interested are rare and sightings are rare, and the cross section of the two is even rarer," he says. "And that's another thing you learn. If you run across a bunch of people who are going out to find a UFO, they will. They will videotape a Cadillac headlight, or an airplane flying over, but they will come back with a UFO. I really shouldn't knock them, they're trying. But it wastes a whole lot of time."

That, in the end, is what it all comes down to. So far, the video evidence for UFOs has been a waste of time. If there were indeed strange craft in our skies, we ought to have some good clear home videos of them by now. That we don't suggests that there are no strange craft in our skies. But that conclusion, of course, is tentative.

I won't say, as some skeptics might, that such things are impossible. Anything is possible. And I would love to see the evidence of a real extraterrestrial craft on video. Once analyzed and certified by experts, a good video of a sharply defined, obviously manufactured, strangely-shaped object doing things that no human-made craft can do would go a long way toward convincing me and many others of the existence of "flying saucers." And certainly such a video would qualify as better proof for the existence of alien visitation than anything yet mustered.

Few UFOs caught on videotape remain unidentified after analysis. But there are some exceptions, and during the last few years Bruce Maccabee, a Navy physicist by day and UFO photo analyst by night, has examined a handful of examples which he believes prove UFOs are capable of flight characteristics — acceleration in particular — far beyond the capabilities of any terrestrial technology.

Among the most remarkable of these videos is one shot by the notorious Ed Walters of Pensacola Beach, Florida. Walters' numerous sightings and photographs over the past decade have been the subject of several books and considerable controversy. As a result, the UFO video that Walters managed to take on July 21, 1995 will not convince any of his critics. But Maccabee has produced an analysis sure to thrill UFO buffs.

The full story of this video actually begins on July 13, 1995 when Walters saw a strange object flash through the sky. Hoping the object would return, he set up his videocamera with its telephoto lens on a tripod in his office and kept up his daily surveillance-by-video until the effort finally paid off. Walters was working at his desk on the morning of the 21st, when he noticed a flash in the sky. So he turned on the camcorder and shortly afterward the object returned.

Its brief reappearance and Walter's description of it are recorded on the videotape: Looking like an inverted layer cake, the UFO appears suddenly at the left of the screen and moves over the Santa Rosa Sound and a line of trees 7,600 feet away on the opposite shore. The object darts rapidly toward center of the screen, reverses direction, and quickly exits left.

When Maccabee received a copy of Walter's video, he was delighted to see that the UFO sequence appeared to show the object's shadow — a roundish, rapidly moving area that slightly darkens the tree line as the object moves back and forth across the screen. "The shadow meant that we could locate the UFO in three dimensions," says Maccabee.

After Jeff Saino computer enhanced the images, Maccabee used an astronomy program to calculate whether the shadow "belonged" to the passing object. He determined that it did. Maccabee found "strong evidence that the darkened area on the trees is, in fact, the shadow of the UFO." This enabled him to also calculate the size of the object. It measured about 27 feet by 13.5 feet, give or take a foot or two.

Maccabee was then able to determine that the UFO had been traveling at about 500 mph, then decelerated to zero, producing about 150 "g's," reversed direction, and departed at about 550 mph. That's probably enough force, notes Maccabee, to "turn a person into soup." It's this acceleration, rather than mere speed, that poses a challenge to physics as we know it. "Speed is not the thing," he adds, "it's how fast it takes you to get up to speed that counts."

The sudden acceleration displayed by this and other UFOs captured on videotape has led Maccabee to believe that this extraordinary flight characteristic may help explain why so many eyewitnesses report UFOs suddenly disappearing. "Maybe the objects are not actually disappearing," notes Maccabee. "Maybe it's simply the inability of the eye to follow them at a high rate of acceleration."

But did Walters capture a genuine UFO on his video? Many don't believe so.

Rex Salisberry is one of them. "I doubt that it's real," says Salisberry, who thoroughly investigated the Walters story for the Mutual UFO Network (MUFON.) "Some of his previous photos did not hold up under our technical scrutiny, and to me, that casts doubt on his other evidence, too."

Maccabee did consider the possibility of a hoax, but after much thought, finally dismissed the idea. "Even a Hollywood special effects person," he states, "would have to be a major genius, use lots of high powered technology, and spend lots of time to get it right."