The second photo exhibition in Houstonist.com's "600 sq mi" theme, this latest show includes the added aspect of examining the less-than-obvious aspects of our fair city. The balance to maintain: focus on Houston while taking aim at the city's unseen aspects. Does the picture reference anything recognizable about the locale? Could the photos provide a treasure map of places specific to here? Or could a similar shot be taken in any city?

The better images are ones that hold closest to the promise of the show's twin themes. Shraddha Shah's "Houston Downtown" offers a new view of the iconic former Enron Building, reflected in water. The curved edges of the building are mirrored and complemented by the rounded outline of a puddle in the street. Effective use of tilt-shift technique by Jay Lee made a custom car show at Reliant Stadium look like the floor of a kid's room. The cluttered interior courtyard of a school under construction is made even busier by the layering of multiple images, collaged together by Brendan Moody (see the photo on Flickr).

Strong compositions make for arresting photos when it's harder to find Houston in them. While frustrating those looking for the actual location, two photographers offered the best abstracted images:

"Space City", originally uploaded by bill barfield.

"Space City" by Bill Barfield: a mirrored highrise reflecting clouds and blue sky while framed by the same sky. It's a perfect execution of a simple (but not simplistic) shot. And, musician Jeff Balke's "Depth" provides a soft-focus look at a dark night of singing.

Many of the remaining images were moderate-to-thoroughly abstracted compositions, taking landscape and architectural elements and removing them from their context. Often ambiguous titles added little to go on and made their actual location a mystery, making it difficult to tie them back to the city.

Like the exhibition's theme, Xnihilo Gallery itself is a bit off the beaten path. Tucked in the back of the Ecclesia worship complex, a walk through the courtyard and cafe leads to the exhibition space. The gallery is an extension of the church's liberal and local outreach (This week's sermon: "Torture is Wrong;" in the cafe's library: "The Tao of Enron"). With a nice balance of relaxed-hipster/ask-us-about-what-Christ-can-do-for-you vibe, it's an intriguing alternative to the white wall art spaces that are the usual venue for exhibitions.

On display until November 23. Free.