Flux profile fit of Flare 2 with M2 r-filter data: the orange curve indicates the best-fit using the flare template aflare1. The black lines show 100 random samples from the Markov chain. The lower panel shows the residuals between the observation and the model. The corresponding posterior probability distribution of the MCMC-fit is shown in Fig. B.1. The lower panel reveals systematic errors in the residuals which might be due to superimposed flares or oscillations. This is further discussed in Sect. 5.