Filament stacks easily fit in light microscope pixels The 2D bounding boxes for a single filament (top left; green), a filament stack with ∼12 NM2 filaments (middle left; magenta), and a doublet of EGFP-NM2A imaged with high-resolution Airyscan imaging (bottom left; black) were overlayed to demonstrate that many NM2 filaments can fit into the light microscopy pixels used throughout this study, consistent with our molecular counting numbers. These numbers should only increase when considering 3D light microscopy voxels and 3D z-stacks.