Deprojections by constant moving bins method of several realizations of a sample projected from an initial Gaussian distribution (N_v ≈ 1200 points, N_s = 25 realizations). We show the mean deprojected distribution (black curve) and the ± 1σ limits (green curves) compared with the initial distribution (red curve). In the left figure, the peak position is 150 km s⁻¹ and its standard deviation 50 km s⁻¹. The deprojection shows no bias with such a velocity peak width. In the right figure, the peak position is 150 km s⁻¹ and the standard deviation 20 km s⁻¹. The deprojection shows a bias with such a narrow velocity peak width. The deprojected velocity peak is too low by ≈ 12% and too wide by ≈20%, although the peak position is precisely recovered to within ≈1%.