Energy resolution obtained with MC simulations for gamma-ray showers at zenith angle distance of 23.6°. The resolution is calculated as an average 68% quantile (orange). Standard deviation of the energy misreconstruction is shown in green. The red line is the resolution value obtained from a tail-less (performed in the range mean ±2 standard deviations) Gaussian fit. The bias of the energy estimation ((E_est − E_true)/E_true) is shown in blue. The thickness of the lines represents the statistical uncertainty. A “gammaness” efficiency cut of 90%, angular distance of <0.2° and “intensity” of >50 p.e. cuts are applied.