Prominence PC observed on November 19, 2011, by SDO/AIA (left) and STEREO A/EUVI (right) in the 171 Å channel. The EUVI image is in log-scale for clarity. Different features are marked with circles in different colors, and two circles of the same color in the two images represent the same feature. The diameter of these circles is 8 arcsec (about 5800 km). The dashed white lines are the longitude and latitude lines of the Carrington coordinates of F4 and F5. The crosses mark some dark patches and small bright spots in the chromosphere near the prominence to avoid confusion.