Dynamic bowties, imaging systems including a bowtie, and methods of imaging including such bowties or systems are provided. A bowtie can be a three-dimensional (3-D) dynamic bowtie and can include a highly-attenuating bowtie (HB) and a weakly-attenuating bowtie (WB). The HB can be filled with a liquid, and the WB can be immersed in the liquid of the HB.