Variation of parameter B of the scaling function for uncertainty in RV (SRV) with effective temperature. The solid line shows results for filter HR15N as a function of Teff (see Sect. 4.1). Dashed lines show results for filters HR10, HR15N and HR21 as a function of the temperature of the template spectrum fitted in the CASU pipeline (see Sect. 2.3). Numbers equal the sample size per bin.