Comparison of here we compare the flux-calibrated spectrum from the observations we made of the spectrophotometric standardstar GD 71 using the same setup as for the Crab pulsar with a model spectrum of the same star. We have plotted the ratio between these observations, and the blue line is a best fit power-law which shows a slight slope which could mean a relative error in flux calibration of ±3% over the entire wavelength region of X-shooter.