There's no way around it, James Benning's Ruhr is a challenging film.

Seven shots compose the two-hour piece, all sourcing imagery from the Ruhr District of North Rhine-Westphalia, Germany, a manufacturing center with roots in the early water-powered stages of the Industrial Revolution. All shots weigh in between 8 minutes and an hour— the camera stationary for each— and vantage points feel like those of inanimate objects; maybe a piece of signage staring off down a tunnel, or a dead-leaf's view of the forest beyond Dusseldorf International, planes passing overhead.

Compared to my past TBA experiences (admittedly, a relatively limited set of experiences), Ruhr most outwardly deals with time— duration of shot being just as important as the subject matter therein.

While these long, uneventful clips serve a purpose, Benning tests his audience in working against cinema's narrative traditions. 8 minutes inside a tunnel are followed by an equal measure inside a steel coking plant; an 18-minute stint in a forest outside Dusseldorf International makes way for a service inside a mosque.

My recognition of slow pace isn't to say that Ruhr is without its pay offs. Rewards are paid at both visual and conceptual levels. There's a mesmerizing shot of a worker sandblasting graffiti from a Richard Serra sculpture, an angular negative space growing inside the colorful layers of unapproved communication. Conceptually, shots focus on the conversion of nature into industrial, civic, religious, and transportation systems, each presenting their own fingerprints in time: a steel mill's glowing-rod minutes or the graffiti's afternoon-long erasure, a mosque's sundial believers or a side street's irregular travelers.

The hour-long final shot of a tower letting out huge billows of smoke works to put the previous scenes into perspective, highlighting the relative timescales that all these nature-taming processes work within. Smoke chokes from the tower, its thick cloud blotting the building out of the sky, then slowly clearing before its dirty weather happens again.

When minute fifty-nine of Building Makes Smoke is over, the previously-tedious shorter shots look like ice cream cones and back rubs in the rearview mirror. It's not really a pleasant journey, but it's a meaningful one: a declaration of relativity, more than anything else. Time is relative. Different tasks breed different clocks. All clocks are simultaneous. I think I get it.

The paradox here though is this: Ruhr's vehicle for communication is also its own best censorship. Audience attrition under the sloth-paced shots began halfway into the third scene and continued throughout. If I had to guess at the dropout rate, I'd say roughly half the audience was still seated when the credits rolled. So, fifty percent?

The reality of it is that 10-minute shots of Nothing Is Really Happening are surmountable repellents; an hour of the same is tenfold the noisome, and all the more risky. I admire Benning's willingness to push duration to its limits, to test his audience, but I wonder if there are less tedious ways to talk about time.

(James Benning's Ruhr is screening this afternoon at 4 pm in the Whitsell Auditorium, located inside the Portland Art Museum at 1219 SW Park. Tickets are $9 for non-members. For more details, click here.)