Haim Weizman is a chemist by trade and an Internet moviemaker on the side.

In his first video, a telegenic narrator in a lab coat swirls a flask as electronic music plays in the background. Created by science and film students at the University of California, San Diego, the video shows a typical recrystallization experiment straight out of Chemistry 101.

The six-minute epic complete with bloopers got 1,205 views on Google Inc.'s YouTube, but the number increased fourfold when the video was posted to SciVee, one of a number of online video-sharing start-ups designed to let scientists broadcast themselves toiling in the laboratory or delivering lectures.

Fans of the niche sites say they help the lay public - and students - understand the scientific process, allow researchers to duplicate one another's results, and may help discourage fraud.

"Anyone in an organic-chemistry class anywhere can now perform this experiment by watching the video. There are so many details that it's hard to describe in a lab manual," said Weizman, a lecturer at UC San Diego. He went on to produce five more lab-training videos.

Researchers who are uploading their experiments and lectures online are discovering filmmaking is more art than science. If the narrators are boring or the image is shaky, viewers will quickly learn to click elsewhere.

Funded by the National Science Foundation, SciVee encourages scholars with a paper hot off the press to make a short video called a "pubcast" highlighting key points. It also accepts unsolicited submissions.

Phil Bourne, a pharmacologist at UC San Diego, launched SciVee this summer after seeing his students hooked on YouTube. Bourne wanted a reputable virtual place where researchers could trade techniques without the potpourri of topics found on general video-sharing sites. "It's quite a quantum leap for scientists to present their research in this way," Bourne said.

The age-old practice of reporting scientific results in peer-reviewed journals or at scientific conferences isn't going away soon. "This is an area we're extremely interested in," said Stewart Wills, online editor of the journal Science, "but we're still in the embryonic stage."

One of the start-up sites - called JoVE, short for the Journal of Visualized Experiments - is the digital mirror to traditional scientific journals, however.

Created last year by a former Harvard postdoctoral student with help from an angel investor, the site has stringent publication rules. On the recommendation of its editorial panel, it dispatches professional videographers to labs doing interesting work. Their footage is edited and approved by the researchers before being posted.

JoVE editor in chief Moshe Pritsker said the Web site grew out of "personal pain." For most of his academic career, he was flustered by what he called the "black hole" of science: Despite attempts by well-intentioned scientists to explain their experiments on paper, some procedures were so complex to mimic that a person must physically explain them.

Pritsker said he once flew to Scotland for a week when he was a doctoral student just to see how a research group performed an embryonic stem-cell technique. He could not help but wonder if there were an easier way. "We need to show our experiments, and

show

, in our [day and] age, means video," Pritsker said.

The popularity of JoVE inspired Siddharth Singh, a computer-science graduate student in India, to start a site in March called LabAction, which focuses on sharing biological techniques. Another site, called DnaTube, was launched in January by Nazir Okur, a molecular-genetics graduate student at the University of Illinois who encourages scientists to upload videos of their studies, lectures and seminars.