Figures 6 and 7 show an industrial building of about 9 m high and a very similar 4-m high plastic greenhouse over the four pan-sharpened orthoimages. It is noted that the objects digitized over the PNOA’s orthoimage (blue line) do not always match well the object boundaries, which can be made out on satellite orthoimagery, due to different off-nadir view angles. This effect is even more noticeable in the objects with higher height and smaller area (see the little building digitized on the northwest corner of Figure 7).