Do their lenses deceive you?

Photography as a faith-based initiative? Not in the 21st century political sense of the term, but as an enterprise requiring, from the start, belief and trust? Absolutely. We take it on faith that what we see in a photograph corresponds to what appeared before the lens, that the image is a trace of reality. This assumption has prevailed since the medium’s earliest days in spite of ever more sophisticated technical means of deception and especially despite the fact that even at its most honest, the photographic image is only a reality, a truth -- fragmentary, compressed, subjective.

Provocative questions about the nature of the medium -- its reliability, its secrets -- permeate the “Immaterial World” exhibition at Stephen Cohen Gallery. The show surveys photography’s use as a chronicler of the supernatural, as a vehicle for attempts to make visible forces, spirits and memories. It is a show about photography as an instrument of faith, packed with examples of how that faith has been earnestly engaged as well as abused.

A large exhibition of similar subject matter (“The Perfect Medium: Photography and the Occult”) appeared last year at the Metropolitan Museum of Art. The 60 pictures in the Stephen Cohen show lack a scholarly framework, or even the barest didactic support, which would be useful, but they are a fascinating group. They echo the contents of the celebrated museum show; true to the subject itself, they serve as its trailing ghost.

Spirit photography emerged in tandem with the broader spiritualist movement in mid-19th century America. Belief in the possibility of contact and communication with the dead motivated the spiritualists. Whether or not spirit photographers subscribed to this belief, it presented a marvelous business opportunity.

Boston-based William Mumler was the first American to create pictures pairing the living with specters of the dead. Frederick Hudson launched the craze in England. Both are well represented in the show by small albumen prints from the 1870s, conventional portraits of the day rendered extraordinary by the presence of second, ghostly figures hovering or standing beside the living subject.

What started out as a joke, in Mumler’s case, developed into a widespread phenomenon ripe with theatricality. Accusations of trickery were continually raised against such work, but in an era defined both by the Civil War and by technological inventions -- such as the telegraph and the X-ray -- allowing access to areas previously unreachable, spirit photography found a ready audience. Never mind that many of the images could be dismissed as accidents caused by light leaks or double exposures; faith kept the practice alive.

The show, installed loosely chronologically, meanders through the 19th century into the 20th, through images of levitating tables, color-soaked auras, and ectoplasm oozing from a medium’s nose, to photographs by Robert Stivers, Dan Estabrook and Clarence John Laughlin, infused with mystery but not necessarily claiming a supernatural pedigree.

In a dark, curtained-off space in the center of the gallery stands one of the show’s most captivating works and one that reveals, with literal transparency, how the medium of photography itself blurs the boundaries between science, art and magic. Stephen Berkman’s “Looking Glass” is a functioning camera obscura made from glass. Like a sleight-of-hand artist proving that there’s nothing up his sleeve, Berkman performs the optical trick that is photography in plain sight: the camera’s lens points toward a skull mounted on a pedestal; an image of the skull appears, upside down, on the ground glass wall of the camera -- at once apparition, trace and fact.

Stephen Cohen Gallery, 7358 Beverly Blvd., (323) 937-5525, through Nov. 4. Closed Sundays and Mondays. www.stephencohengallery.com

There’s a message amid the humor

What do Al Gore, Dracula, Madonna, Hitler and Abraham Lincoln have in common? They all make cameo appearances in “Empire 2 (Survival),” a hilarious, horrifying painting by David Quan and Colin Chillag. The Phoenix-based painters feature five additional works in their show at Angstrom (formerly Q.E.D.), but “Empire 2” is so rich with political commentary, cultural critique, crude humor and language play that once it ensnares you, you may not make it to the others.

The painting, just larger than 6 by 8 feet, is a feast of irreverence, a sprawling take on the American appetite for violence and spectacle. The action takes place in Iraq, by way of the Roman Coliseum, as filtered through American media. The single lion that appears in the crumbling arena occupying half of the canvas is a docile creature, spreading its jaws for a circus trainer. Mayhem erupts all around them in the form of bubble-headed cartoon figures that stab, shoot, kick, spear and otherwise hammer away at one another. In the midst of it all, cheerleaders in chadors (“Jihotties”) raise red pompoms and a generic, blank-faced political couple poses for the cameras. In one of the box seats on the upper tier of the packed house perches a vulture, wearing a business suit and declaiming, “Where you see tragedy, I see opportunity.”

Outside the stadium, oil pipelines gush blood, a bulldozer shoves piles of corpses off to one side, and propaganda, American-style (an I Love New York T-shirt, a pack of Twizzlers red licorice), parachutes down from above. Quan and Chillag are savvy at sampling different visual idioms, reworking iconic war photographs, adapting television formulas and capturing the graphic immediacy of the comics page. Their satire is beautifully, painfully barbed, trading on familiar symbolism. Another of many examples: On one of the upper arcades of the arena, a janitor sweeps out a clutter of skulls. Below, where they are destined to fall, stands Uncle Sam and one of the little blue cartoon figures. The blue guy pleads to the emblem of American patriotism, “Please, stop,” but Uncle Sam hushes him with a finger to his lips as pools of dark blood spread at his feet.

Angstrom Gallery, 2622 S. La Cienega Blvd., (310) 204-3334, through Oct. 14. Closed Sundays and Mondays. www.angstromgallery.com

Making aerial landscapes playful

Aerial views distort and abstract. There’s something thrillingly unnatural about them, especially because they’re afforded largely by technological achievements of the modern era: jumbo jets and skyscrapers. Viewing a city from above, details slide away and geometric order becomes more pronounced; idiosyncrasies blur together as pattern takes over.

In her enjoyable recent drawings at Cirrus, Susan Logoreci also injects the aerial landscape with elasticity and playfulness, an organic fluidity usually more apparent at ground level. She works in colored pencil, articulating buildings, shadows and greenery as solid patches of cement gray, roof tile red and cypress green, fitted together as tightly as mosaic pieces. Streets and undeveloped land she leaves bare, supplying some visual breathing room and dramatic contrasts.

In “Beach,” for instance, a wedge of white paper representing the shore offsets the densely faceted built landscape adjacent. “213212” serves as an emblematic map of the U.S., with its horizontal spread of L.A. homes and apartment buildings on the left dissolving into the vertical spires of New York residential and office towers on the right.

Logoreci, based in Los Angeles, reduces the built landscape to pattern and rhythm, a patchwork stitched of colored bits. Her drawings are charming in their irregularity, the way rows of windows swell and tilt, every bit of each city drawn -- and savored -- by hand.

Cirrus Gallery, 542 S. Alameda St., (213) 680-3473, through Oct. 28. Closed Sundays, Mondays. www.cirrusgallery.com

The mundane confronts the epic

For the last decade, Toba Khedoori has had a large presence on the international drawing and painting scene, not least because she works on a monumental scale. Her pieces typically measure 20 feet in width, sometimes more, the size amplified by the starkness of her imagery -- spare, vacant architectural spaces and structures such as railings, doors, bridges, fences, walls. The physical presence of her work is built largely on the visceral power of absence.

Khedoori’s new paintings at Regen Projects -- her first solo show in L.A. since a memorable 1997 exhibition at the Museum of Contemporary Art -- expand upon familiar territory for the artist, to mixed effect. In several of the six paintings on paper, Khedoori orchestrates tension between affront and invitation, barrier and window. In two of them, she sheathes the surface in thick strokes of waxed pigment, in one case black and in the other a dirty white. In the center of each work, she has painted rows of small but deep rectangular openings, as if perforating the thick wall with a geometric screen. The permeability and luminosity as well as the illusionism of the windows contrast dramatically with the more process-oriented reiteration of the paper’s surface.

Another work is, again, all black, but for a deftly rendered gleaming fire in a fireplace, painted to scale, at eye level. The comfort of the hearth pulls the eye and body close, while the methodical horizontal strokes covering the rest of the painted surface defy such intimacy.

An untitled painting of clouds introduces a note of romanticism. Another painting, a vast white surface freckled with black spots, looks like a celestial panorama with values reversed. Bits of grit, stray staples and hair embedded in the waxy surfaces assert the raw physicality of Khedoori’s materials and methods. The confrontations she has staged between the mundane and epic are graphically striking, but throughout, affectation threatens to overwhelm effect.

Regen Projects, 633 N. Almont Drive, (310) 276-5424, through Oct. 14. Closed Sundays and Mondays.