a) Raw image from the “Favorite+” region: the Venus disk is clearly visible as the horizontal dark strip at the center of the image, in addition to the fringe pattern (sloping dark lines), the bad pixel area in the upper left corner, and the gain jump between the upper and lower CCD chips at the center of the frame. Strong solar and weak telluric absorption lines appear as vertical dark stripes. b) Reduced image, after flatfielding. Clearly visible are the solar and telluric absorption lines and the gain jump between the CCDs.