Jacqueline Galke has heard the story before. A young student who died of pneumonia at Patapsco Female Institute before her parents could reach her wanders the grounds of the former 19th-century school.

Nervous teens hang out there in hopes of a sighting. Ghost hunters stop by snapping random photographs.

"We realize people think that it's a haunted site," said Galke, executive director of the Patapsco Female Institute Historic Park in Ellicott City. "Do we care? No. It's been considered a haunted site at least for the last 25 years."

If the pursuit of ghosts seems a frivolous curiosity to Galke, others take it more seriously - ghost hunters who believe in what they see and ghost debunkers who worry about pseudoscience.

Timothy Kerins and Ken Rathburn, two computer network controllers have taken about 100 photographs over five visits to the institute in June and July and say they've come up with possible evidence of ghostly presence floating around the grassy fields of the stabilized ruins.

Shot with Kerins' digital camera, the images reveal what the pair call "orbs," or circular, floating illuminated objects and globs of white streaks that they see as resembling a woman in white Victorian dress.

"We saw lights coming up," said Kerins, 36, a Timonium resident. "I didn't know if it was from lens flare [reflection of source light in a straight line] or a light back in the trees. Then we saw they were showing up next to objects or in photos we took of each other. In some pictures, they were appearing where there was no light."

Although the images are of different sizes, he said, they are translucent and have texture.

On their next visit, the pair said they were stunned by the image of a white luminary taken by Rathburn while he extended the camera in front of him. "You're not going to believe this picture," Rathburn said.

If Rathburn and Kerins are entranced, professional ghostbuster Joe Nickell believes speculation about ghostly orbs and luminaries is a product of wishful thinking.

"It has all the earmarks of superstition, ignorance and pseudo-science," said Nickell, senior research fellow at the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP) based in Amherst, N.Y., and science writer for its publication, Skeptical Inquirer magazine.

"Science has never authenticated a single ghost," he said. "Most of which is claimed as supernatural and paranormal is negative evidence. They say, `We don't know what this is. It's unexplained phenomena.' To claim you don't know what something is and then claim it's paranormal or supernatural is lapse in logic.

"It's arguing from ignorance. If you heard a funny noise in a house, you can't claim that's a ghost because you don't know what it was. And if you don't know, you don't know. Period. I've been in more haunted homes than Casper. These phenomena don't happen when I'm around."

Nor, said Nickell, can anyone determine which are authentic ghost photos because there are no genuine ghost photo standards with which to compare them.

He attributed ghost photos of transparent people to double exposure, reflections or hoaxes, while photos of "nonpeople-looking ghosts" such as orbs, streaks, mists, strands or bursts of light are "glitches" in the photography process. Those, he said, are more commonly caused by a flash and anything that gets in between the camera lens and scene, which can create a glitch.

Orbs, he said, are particles of dust or droplets of moisture close to the lens, foggy breath on a cold night bouncing the off the flash, a puff of cigarette smoke, a flying insect, strands of hanging hair, one's fingertip, foliage, jewelry or a camera wrist strap.

Galke sides with Nickell.

"The ghosts of the PFI are all fiction," she said. "I've never seen a ghost and I'm really disappointed. I've been affiliated with PFI for about six years. I don't know anyone else here who's seen a ghost."

Despite her skepticism, Galke has arranged for 15 members of the Maryland Ghost & Spirit Association, to spend the night Nov. 16 at PFI after Kerins and Rathburn consulted with the group's founder, Beverly Litsinger. "I want to help them to dispel the myth and fallacies," Galke said. "I think it's an important thing to do so it's not such a mystery."

Litsinger, whose association has 400 members, plans to bring along ghost-hunting equipment including a video camera, night scopes, thermal scanners and electromagnetic detection.

"Ghosts have a lot of electromagnetic energy," said Litsinger, 49, a Randallstown consultant to nonprofit organizations.

Ghost skeptic Nickell said thermal scanners and electromagnetic detectors are not designed to catch ghosts and should not be used to try.

Litsinger claims that people have seen full-body apparitions of the student, whom she said, hated PFI and wanted her parents to get her out. "Some ghosts are trapped because of unfulfilled lives," she said. "She's an unhappy soul. Someone has to tell her she has the ability to leave. She's probably not aware she's dead."

PFI isn't Ellicott City's only haunted site, according to Litsinger. "Howard County is covered with ghosts," she said.

She points to the Mount Ida Mansion, down the hill from PFI, where Litsinger says its last resident, Ida Tyson, can be heard rattling the large set of key rings she had carried. Folks also claim, she said, that they can hear doors slamming in the old firehouse on Main Street or furniture being moved around upstairs in the former Moose Lodge nearby.

In fact, the Howard County Tourism Council leads tours of the historic district based on the book The Hauntings of Ellicott Mills, written by the council's executive director Melissa Arnold.

Other reports, she said, are from former employees of the old courthouse in Ellicott City who claimed they heard the jingling of bells at the front door, even though no one was there and the door was locked. Then there are the orbs that showed up on photographs taken in total darkness of a former opera house in the upper floors of the Forget-Me-Not Factory.