Root square error between deconvolved images and OASIS+albedo model. Each of the six subfigures corresponds to one of the observing epoch. Evolution of the error with respect to the α and β parameters is then visible. For each epoch, optimal values of α and β are the onesthat minimise the error. Invalid pixels (missing albedo) were removed for error computation. However, all pixels (inside and outside the asteroid) are considered to take into account the residual blurring after eventual incomplete deconvolution. Errors have also been divided by the flux of each Vesta observation so they reach comparable values between the different epochs.