Error as a function of ρ, for LIO (top panel) and SIO (medium panel). Here, SC: simple correction; REG and NR: regularized and non-regularized algorithms; raw (red curves) and deb (blue curves): raw data and data after bias subtraction, respectively. Vertical dashed lines represent the geometrical limits of vignetting. Bottom panel: zoom on the error of the above figures. Raw data: red and magenta curves. Bias subtracted data: Blue and cyan curves. See more details in the text.