One typically thinks of a screen print as a puzzle of distinct, flatly colored shapes. But few of the works in Approaching Zero - At the Frontier of Contemporary Printmaking have that texture or aesthetic. The group show, now on view at Kala Gallery (2990 San Pablo Ave., Berkeley), brings together artists from around the world whose compositions push the medium of printmaking to its limits. Included works by Koseki Ono appear simply as color blocks from a distance, but are stunning close-up. By screen-printing tiny dots on a canvas hundreds of times in various colors, he forms a three-dimensional landscape of miniscule rainbow cylinders that form a mesmerizing, multicolored surface. Meanwhile, Miguel A. Aragón uses a unique laser-cut and cardboard technique to create gently burnt renderings that appear to be embossed onto the paper. Appropriating newspaper photos of murders that took place in his hometown of Ciudad Juárez, Mexico, Aragón works to metaphorically manifest their effects on the psyche. Other artists include Stella Ebner, Zarina Hashmi, Walter Jule, and Katsutoshi Yuasa.