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We discuss a recent paper by Schlichenmaier & Franz (SF; 2013, A&A, 555,A84), in which the claim is made that the penumbral dark downflows detected forthe first time with the Swedish 1-m Solar Telescope (SST) by Scharmer et al.and Joshi et al. could be produced by overcompensation for straylight. We showthat the analysis of SF is fundamentally flawed, because it ignores theconstraints on the strength of such straylight from 3D convection simulationsand on the spatial extent of the straylight point spread function from themeasured minimum intensity in the sunspot umbra. Furthermore, we show that theclaim made by SF, that the spatial straylight of Hinode is less than 10%, isfalse. We conclude that the analysis of SF is of no relevance in relation tothe straylight compensation method applied to the SST data.

Response to "Stray-light correction in 2D spectroscopy" by R. Schlichenmaier and M. Franz