Decoding Scientific Experimental Images: The SPUR Benchmark for Perception, Understanding, and Reasoning. - Junpeng Ding; Zichen Tang; Haihong E; Mengyuan Ji; Yang Liu; Haolin Tian; Haiyang Sun; Pengqi Sun; Yang Xu; Yichen Liu; Haocheng Gao; Zijie Xi; et al. (CoRR, 2026)