JOPLIN, Mo. — I am an unapologetic movie geek. I track production stories, parse box office numbers and follow technological advances. I have spent a good portion of my life inside movie auditoriums, and another hefty chunk watching at home.

This makes me the ideal audience member for “Side By Side,” a documentary chronicling the changeover from 35mm to digital filmmaking.

“Side,” available in limited release in theaters and for rent on iTunes, follows interviewer Keanu Reeves as he talks to various directors, cinematographers, editors, producers and actors about the transition from film to digital. It is a surprisingly divisive topic -- one that generates a very passionate, well-argued debate.

The movie won’t appeal to everyone. After all, the average moviegoer could care less whether a movie was created with celluloid or ones and zeroes. But what the film also offers is a glimpse inside the creative process of some of Hollywood’s heaviest hitters.

It’s not surprising to see visual artists such as James Cameron and George Lucas preaching the praises of digital filmmaking. With the new advances, they have been able to create amazing looking worlds that would otherwise have been impossible with the old technology.

And because Lucas and Cameron continue to insist on writing their own screenplays, when history and finished products have shown that their skills don’t necessarily rest in writing, their finished product benefits from the visual distractions allowed by the new methods.

It is more interesting to look at the opinions of unique story-driven directors who don’t rely on the gimmickry allowed by digital cameras to get a real feel for the pros and cons of the conversion.

The biggest opponent of the technology in terms of clout would be Christopher Nolan, whose latest film, “The Dark Knight Rises,” was filmed in 35mm. Nolan and his cinematographer Wally Pfister were both interviewed, and both made impassioned arguments for the warmth, depth and feeling that digital cameras aren’t able to replicate.

The reasoning was valid, if futile, as both acknowledged that their days of being able to work in the old medium were coming to an end. But they know that, when the battle is over, a lesser format will be the victor. As Pfister says in the film, “It’s really sad right now to see cameras that record imagery in an inferior way start to take over film. I’m not gonna trade my oil paints for a set of crayons.”

Director David Fincher, on the other hand, is a strong proponent of digital cinema, which is not surprising considering the number of takes he prefers with each scene. His arguments about the ease of setup and ability to continually film without downtime to change magazines are very valid. They also lead to a funny story about Robert Downey Jr.’s silent protest when filming “Zodiac” and finding that his time to recoup, regroup and re-energize had been all but done away with when the downtime was eliminated.

One part of the new digital technology that was almost universally disliked was the ability to film and present in 3-D. Aside from an informative glimpse into Cameron’s processes in making “Avatar,” there was little positive said about what many regarded as a novelty, and a tired one at that. As Fincher said, “There will be people who not only kill the goose that lays the golden egg, but they’ll sodomize it first.”

I’m still a proponent of 35mm over digital, both in filming and presentation, if only because there’s a warmth and lack of sterility to film that digital has yet to be able to create. But even I realize that the advantages of the new will quickly outweigh the old.

As one director said (and many who have watched film projected by poorly trained and mostly indifferent hourly employees can attest to), digital eliminates the scratched frames, broken film and poor splices that were a testament to either wear and tear or incompetence. That’s always a good thing.

But for some, the trade-off won’t be all positive. One particularly scary thought with the new technology is that the preservation of movies themselves might be more endangered. With each new generation of advancement, film backups must be updated to keep up with the changes, or else the work will be lost to the past.

To play 35mm, all that is required is a projector. One can play film from the dawn of cinema or the latest release using the same equipment.

With digital storage, the storage must transition with the technology to keep it accessible. And though a film print may break or scratch, it will still be viewable. Should a hard drive seize or crash, the work of hundreds of people costing millions of dollars or more could be lost.

“Side by Side” is a snapshot of a transition -- a document of an era where the sun is setting on over a century of history. Reeves, though still sounding a little surfer-ish, asks compelling and driving questions that get at the heart of the divide between the two standards. It won’t interest everyone, but it will enlighten.