Viewing geometry and multi-scale context in the 171 Å channel. Top left: Relative positions of SDO (near Earth) and STEREO-A in the heliographic Stonyhurst frame at the time of observation. Top middle: Full-disk AIA 171 Å image with the selected limb segment shown in red. Top right: Zoomed AIA view of the limb region containing the two prominences, with arrows marking the prominence footpoints. Bottom left: Corresponding full-disk STEREO-A/EUVI 171 Å image with the projected limb segment. Bottom middle: Intermediate EUVI zoom providing additional spatial context. Bottom right: Tight EUVI zoom of the prominence region, with arrows indicating the same footpoints as in the AIA panel.