ORONO – You don’t see them. You don’t think about them. But when the house lights dim and the stage lights come up, an invisible cast darts about, figures just as important as the actors in any theater production.

And while the actors may be the axis of a play’s imagined world, it’s these “out-of-sight-out-of-mind” people working quietly behind the scenes who create the literal scene – whether it’s a door slamming or warm afternoon light spilling through a window – in plays. The stage crew’s contributions range widely from running the lights and sound – adding color, character and effect to scenes – to wrangling props to making sure things happen on time.

Last week, four eastern Maine high school students got a crash course and honed their backstage skills at the annual Maine Center for the Arts Summer Theater Tech Camp. The five-day camp focused on the basics: sound, lighting and even knot tying.

“This is something where they can see what it’s all about,” said Stephen Wicks, MCA’s education and outreach coordinator and the program’s creator. “And to see if they are interested in going further, both for the short and the long term.”

In its fourth year, the MCA program has averaged about eight participants each summer from high schools within a 100-mile radius of the Orono campus. And while many of those schools have strong theater programs, Wicks said the camp’s goal is to serve those who both do and don’t have access to such instruction.

With the group smaller this year, participants got almost one-on-one instruction. On Wednesday, they spent the afternoon session learning about the fine art of lighting from MCA assistant technical director Scott Stitham and two of his staffers. The teens learned to program light cues into a computer, operate the control board and spot-check their work.

“I think more people should get involved with tech work,” Chelsea Castonguay said on break from the programming cues. “Because without us, there wouldn’t be a show.”

Castonguay, who’ll be a senior this year at Orono High School, said she came to this year’s camp because she’s planning to do stage management for the school’s theatrical productions this year.

She, like her fellow campers, participates for another reason, too: to bring back what they learn to school and pass it on to peers and underclassmen.

This year’s program had a new element. At week’s end, the tech campers teamed up with teen actors from Penobscot Theatre’s summer acting camp to stage an end-of-term performance. The brief afternoon show last Friday gave the teens a chance to try out their newly acquired tech skills while three actors delivered a short series of monologues.

“It’s an unsung hero sort of thing,” said Ian Grady, who’ll be a junior this year at Bucksport High School and has previous experience acting, including improv comedy with a troupe of peers called Caught in the Act. “It’s learning how to do all the stuff that has to happen before I can what I do.”

Grady said he plans to continue on in theater, and the camp has diversified his theatrical skills. “That’s why I asked to come, so that I can add this to the resume,” he said. “It’s another skill to have when I’m looking for jobs maybe next summer.”

George Bragdon can be reached at gbragdon@bangordailynews.net.