Tom Hamilton and Tripp Rhame just spent a muggy week at an abandoned prison, dodging copperheads, feral dogs and hypodermic needles. They couldn’t be more thrilled.

“It’s exhilarating,” Hamilton said. He and Rhame are co-owners of Midtown-based Spitfire Studios and co-producers of “The Circle,” its first feature film. The company originally was a commercial photography studio launched by Hamilton in 1998. He and Rhame joined forces several years ago and, bolstered by the state’s tax incentives for the film industry, decided to switch gears and pursue filmmaking.

“It’s the difference between us making this film and not,” Hamilton said of the state’s film-friendly tax policies. “We’re the poster child for what that program was intended to do. We’re a little hometown company that has grown.”

On its busiest days, “The Circle” employed a total of about 60 cast and crew members, mostly local residents with some out-of-town acting and writing talent.

“It’s awesome,” Rhame said during an interview on the movie set the other day. “My friends are in it. My friends are working on it. I kind of feel like this happened for a reason.”

“The Circle” is about a group of friends who end up at a haunted prison. It filmed at a historic house in Snellville and at the Atlanta Prison Farm site, an abandoned, burned-out and partially demolished building that sits off Key Road in southeast Atlanta amid acres of wilderness. (They weren’t charged for use of the facility, but did have to pay for off-duty police officers to maintain security.) The crew had to clean up quite a bit before filming could start, discarding needles and other debris that suggest the facility isn’t entirely abandoned, and were advised to keep an eye out for assorted wildlife.

“Nobody got bit,” Hamilton said this week, having wrapped filming at the site.

“By an animal,” Rhame quipped.

“The Circle” cast includes Riley Smith of the modern “90210,” Elimu Nelson, who’s appeared on episodes of “House of Lies” and “The Game,” and Chelsey Crisp, who has been seen on episodes of “Mike & Molly,” “Rizzoli & Isles” and “CSI: Miami,” among other shows. She’s been impressed with the caliber of talent in Atlanta, saying, “They’ve been the nicest people I’ve ever worked with.” She also applauded what had to be the most perfect set an independent film could have hoped for.

“It’s an amazing place to film,” she said of the derelict, graffiti-covered former prison. “It’s very creepy.”

Local actor Raj Kala, who has nabbed roles on locally made feature films including the Will Ferrell comedy “Anchorman 2” and “The Good Lie” with Reese Witherspoon, plays a scary bad guy in “The Circle.”

“The acting bug bit me three years ago,” said Kala, who also has worked as a musician.

Shooting for “The Circle” began May 8, and the project is wrapping up this week with some interior work. Next it heads into postproduction work with a scheduled completion date of later this year. Hamilton and Rhame plan to enter it in various film festivals in hopes it’ll be picked up and eventually distributed to a wide audience. The project had a budget of between $530,000 and $540,000, but partly because of that serendipitously spooky set, Hamilton expects a bigger budget feel.

“We could not have spent $5 million and had it look this good,” he said. “We’ll put $1 million-plus of production value on the screen. We call it a feature film even though it’s independently financed.”