Performance of NNES-based adaptive global thresholding and its prediction model (3D). (a) The NNES curve of the same sample set as Fig. S1. While they vary in actin features (density, bundling, etc.), they have very similar NNES shape. (b) The correlation of coarse background (evaluated by an approach mimicking 2D MGT) vs the peak of NNE count for individual samples and corresponding coarse background prediction model. As suggested by NNES curve shape, they have very similar peak as well as coarse background, which represents the norm of sensor performance in 3D imaging (2D projection therefore is distorted by information loss). Therefore, we directly used a simple proportional function to establish the regression model.