Astronomy has a long tradition of translating data into different visual representations and scholars have noted a division between ‘pretty pictures’ and scientific images. A series of drawings and engravings of M51 derived from Lord Rosse’s observations at Birr Castle and Hubble Space Telescope images of the same object offer an opportunity to examine shifts in the object’s representation within a given period, as well as over the long history of observing it. This demonstrates both the consistent interest of astronomy in structure and improved resolution, as well as the subjective treatment of light and color. Furthermore, while the distinction between ‘pretty pictures’ and scientific images offers a starting point for analyzing the translations within a given period, the line between the two blurs, suggesting the complexity of aesthetic choices within astronomical images.