Calibration tools for very accurate measurements: a new calibration is required whenever you insert an extra optical elements in your setup (like collimators, Beam-Expander etc.) and/or in presence of temperature variations (the standard Shack-Hartmann camera itself has temperature fluctuations). For this reason, our wavefront sensors do not use pre-calibrate images but we provide you with the tools for a quick acquisition of a calibration image whenever you require it