An orchestra is defined as a large instrumental ensemble typical of classical music. An orchestra features bass, brass, strings, woodwinds, and percussions. In the list given above, the section that is not one of the four groups in the orchestral palette is the voices. The answer would be "voices".
Well the artist David Hockney believed that Johannes Vermer and other used these devices such as the camera obscura to help them achieve their perceptive in achievement
