Abstract: In order to improve the disadvantages of many redundant information and more exposure time in traditional multi-exposure technology on optimal exposure image,a method of acquisition minimal-bracketing sets is proposed in this paper.According to this method,the dynamic range of the target camera in the radiation domain can be calculated using image sequence from the maximum exposure to the minimum exposure captured by the target camera.And this range is used as the benchmark of the target camera.When we capture the multi-exposure images,the minimal-bracketing sets based on the optimal exposure of the target scene can be obtained through calculating the dynamic range of the optimal exposure image of the target scene and the maximum and the minimum irradiation of the target scene.The experimental results of high dynamic range images synthesized from different sets using typical high dynamic range scenes show,compared with the traditional bracketing sets acquisition method,the proposed method can effectively reduce not only the number of low dynamic range images in high dynamic range imaging but the total capture time of multi-exposure images as well as saving storage space in case of ensuring the quality of high dynamic range images.