The recent trend of incorporating more visuals into communication challenges technical communicators, who must now possess both verbal and visual literacy. Despite all the recent scholarship on visual aspects of technical communication, technical communicators lack thorough guidelines for selecting and composing effective images that convey thematic and conceptual information, or what Schriver calls "stage-setting" images. This article reviews existing literature in visual communication and reports results of a study that assessed readers' opinions of themes conveyed by specific example images. It then suggests that the rhetorical tropes of metonymy and synecdoche can be used to identify images for conveying certain themes, and that successful stage-setting images will show intrinsic, not extrinsic, relationships to their thematic subject matter.