Two fluorescently labeled filaments run 130 nm apart — well inside the ≈250 nm Abbe diffraction limit of a visible-light microscope. Light every fluorophore at once (Conventional) and each molecule's point-spread-function blob spans the whole gap: the two lines merge into a single blurry band, and the structure is lost.
STORM/PALM instead only lets a random sparse subset of molecules fluoresce each frame — few enough that their blobs rarely overlap. Each isolated blob's true center is fit precisely (its "localization"), plotted as a pinpoint dot, and the dot is added to a running reconstruction. Repeat over thousands of frames with a different random subset each time, and the accumulated dots resolve the two filaments distinctly.
resolution(N) ≈ σ_loc·2.3 + (limit − σ_loc·2.3)·e^(−N/800)
- Blink density — probability each molecule fluoresces on a given frame; too high and blobs start overlapping again, corrupting localizations.
- Localization precision (σ) — how tightly each isolated blob's center can be fit; sets the noise floor of the final image.
- Acquisition speed — simulated frames processed per animation tick.