Fig. 2.

Limits of the accuracy of the parameter estimates as a function of the speed of a linearly moving object. (a) Practical limits of x₀ (—) and y₀ (– · –). (b) Practical limit of φ and (c) of v. (○) corresponds to the noise-free case and (◇) corresponds to the case where Poisson noise ( ${\mathrm{\Lambda }}_0^{(2)}$) of 2 photons/pixel/s and Gaussian noise (σ_k) of 4 e⁻/pixel are present. Their corresponding fundamental limits (*) are included as the references. For the object in all plots σ = 83 nm, magnification M = 100, its direction of movement φ = 30°, and its starting coordinates are (x₀, y₀) = (−268.7, −268.7) nm. The photon detection rate ${\mathrm{\Lambda }}_0^{(1)}=1000\text{photons}/\text{s}$, acquisition time is 0.2 s, pixel size is 4.03 μm × 4.03 μm and the array size is 31 × 31 pixels.