Gareth Edwards won't reveal the budget for Monsters, his thriftily constructed feature debut about two young Americans trying to buy their way back from Mexico following an alien occupation. Yet he’s quick to acknowledge that his acclaimed sci-fi fantasy might never have been possible without advances in filmmaking technology usually associated with big-budget blockbusters like last year’s Avatar.

“It used to be that if you wanted to make a movie with professional-looking computer graphics, you needed equipment that cost half a million pounds,” says the British director, 35, a former visual-effects engineer whose feature reportedly cost $15,000 to make, with its most inventive sequences produced on his laptop.

“But as technology has made computers faster, it was only a matter of time before this monopoly of people with millions to spend was broken. The computer on my desk is as powerful as the one they animated Avatar on, just not the one they used to render it. So the playing field has really been leveled – it’s about who’s got the best ideas, not who has the most money.”

Despite his special-effects background, Edwards believes too many filmmakers have come to rely on computer graphics as a crutch, preferring to render digitally real-life phenomena that would be more easily filmed the old-fashioned way. It’s a trend that has given CGI a bad name.

“Some people ask too much of the graphics,” he says. “They try to computer-generate trees, water effects or dust clouds – things that would look better if you just filmed them for real. You can do anything with computers, but why would you? Technically I could walk from Alaska to Siberia, but you’d have to be an idiot to do it. It’s easier to fly.”

Edwards cites Christopher Nolan’s Inception as proof that big-ticket productions can still get it right, emphasizing ideas over effects and only relying on computers as a last resort. And that, he says, is how he approached Monsters.

Did his budget dictate restraint in filming his characters' arduous road trip, a journey inspired partly by his grandparents’ experiences in post-World War II England, where the reconstruction effort seemed omnipresent? Yes, says Edwards, but it never compromised his storytelling.

“If I’d had $10 more, it would have been a different movie,” he says. “It might have ruined the movie. But I tried to approach it like, ‘Let’s tell a story. Maybe a computer could help.’ Rather than, ‘What can computers do? Great, how can we tell a story with them?’ That’s the complete wrong way to make a movie. That’s when technology gets abused.”