A gallery in London is challenging what the director calls the "habit" of art appreciation with an exhibition of work that is actually difficult to see.

Pieces include a labyrinth of infrared sensors, a room cooled by air conditioners using water that washed the dead of Mexico's drug wars, and invisible ink paintings - some dating back to the 1950s.

Director Ralph Rugoff says the exhibition could serve as a "palatte cleanser" in a season of spectacles, from the Queen's Diamond Jubilee to the Olympics, but the $12 admission might leave some visitors wondering what they came for.

Charlie Angela reports from London.

Source: Al Jazeera