Magnetic energy spectra of the vertical flux densities, without and with various amounts of random noise added to the original data, for which the measurement noise σ_obs is 1.4 G. The five curves that deviate increasingly from the original spectrum for the largest wave numbers represent added noise with standard deviations of 1, 2, 4, 8, and 16 × σ_obs. The dotted lines mark the boundaries of the observed spectrum, determined to the right by the Hinode resolution (0.232 Mm), to the left by the effective slit length (104 Mm).