Production sound mixers on the sets of this year’s action films found themselves everywhere from rough seas to the highest elevations in New Mexico with one goal at hand — get the kind of sound that makes it all believable and the kind of dialogue that’s easy to understand.

For Chris Munro, nommed in sound mixing for his work on “Captain Phillips,” that meant fighting waves and salt water for days on end. Though he’d worked with helmer Paul Greengrass before on “United 93,” there were still unexpected challenges.

“Members of our crew could only stay inside the yellow lifeboat for a little while at a time before becoming extremely seasick,” Munro says. “We were carrying the lightest equipment we could and these guys were all very experienced, but it really didn’t matter once you were in that thing.”

Munro believes it was vital to get sound that conveyed the claustrophobia of that space so they toughed it out. And advances in microphone and recording technology over the past few years made it possible to precisely capture sound and separate tracks later. But production mixers still have to go out on the sea to get those sounds on location.

Production sound mixer David Brownlow ­— also nommed — came to the set of “Lone Survivor” with substantial documentary experience. He leaned on those techniques to get raw, realistic battle sound while still capturing clean dialogue.

“(Director) Peter Berg would have us all get prepared and ready to go in the morning and then we’d just shoot the thing like we were in front of a live audience,” Brownlow says.

“I was working with a crew that had lots of experience just going with the action so we were able to capture a sense of immediacy.”

Normally, on a narrative feature like “Lone Survivor,” retakes are possible — theoretically unlike a catch-it-while-it-happens live event, or even a reality series such as “Deadliest Catch.”

But budget and schedule restraints on “Lone Survivor” meant resets and retakes were onerous, so Brownlow had to get the sound he needed the first time around. The mixer’s crew had all the actors on wireless mics on the outside of their clothing so that movement and explosions could be captured. His crew also used mics that could cancel out explosion sounds to capture dialogue.

“In situations like this you’re relying on your crew because your boom man has to know exactly where to go,” says Brownlow. “It’s really a crap shoot at times but the gods were with us and somehow it worked.”