In high-speed electrophotographic (EP) printing, clustered dot halftone screens are required to achieve consistent print quality. However, the shape of the spot in the screen plays a critical role in the quality of the printed output. For example, dot gain can cause unpleasant artifacts in midtone regions. We discuss a new spot function for EP systems that addresses artifacts from midtone dot gain and printer stress, demonstrating its suitability for use in a range of bitonal production printers.