Smart Focus is a graphical tool for standardized preprocessing of specimen images. The software removes image backgrounds, centers and crops the main object, and preserves the original aspect ratio to produce consistent inputs for downstream analysis. It supports interactive foreground/background annotation, batch processing of large image collections, and GPU-accelerated segmentation using the Segment Anything Model 2. The application was developed to support taxonomic image datasets by reducing background variation and positional bias while maintaining reproducibility of preprocessing steps. It was used in the study of morphologically similar freshwater snails (Radomaniola), but is applicable to a wide range of biological imaging workflows. Key features include interactive segmentation refinement, automated dataset traversal, preservation of directory structure, and reproducible preprocessing settings. The software is implemented in Python and designed to operate on standard desktop hardware.