WITNESSES OF TIME by Flor Garduno , introduction by Carlos Fuentes (Thames and Hudson: $40; 72 pp.) Flor Garduno is one of a handful of Latino photographers recording the remote and unseen corners of Latin America. All of the photographs are of the Indian peoples in Mexico, Peru, Guatemala, Bolivia and Ecuador. What separates Garduno from her contemporaries, among them Sebastiao Salgado, Pedro Meyer and Graciela Iterbide, is that her photographs are uncluttered by busy backgrounds that obstruct the overall intent of the image. Shot on black-and-white film, the images are rich in tone and texture. Whether it be a young girl with flowers or a scenic view, the 70 plates convey a sense of tranquility. The most effective photographs are those that are not posed. They capture the essence of the various cultures without the contrived usage of a mask, sacrifice or crucifix. Photographers sometimes try too hard to convey specific ideas about religion, the conquest and rituals. The Latin American culture is so rich that it is better to let the natural setting tell the story. Garduno's photography does this splendidly.