Information to the creation of the Signal to Noise Calculator for the TIGRE

For the signal to noise (S/N) calculator, the S/N of 12 objects with different B-V values obtained from the reduction pipeline are used. At first, a median fit is used to find outliers. This outliers are replaced with the values form the median fit. Then the position of the maxima in each order are estimated. In a range of ± 2Δλ around the maxima position, the mean S/N is calculated. The mean S/N values are time normalised and converted the mean S/N in the Vega S/N scale. Next, these values are smooth slightly and converted into the same wavelength grid. Finally, the S/N vs. B-V are fitted for each wavelength point.

Information to the used spectra

The Δλ is ≈ 4 pixel in the spectrum. The range of the B-V is from -0.11 mag to 1.56 mag. The mean seeing during the observations was 3.6'' with a standard deviation of 0.4''.