Time sequence of SOHO/MDI continuum images of the whole active region NOAA 10781 between July 2 and 6 of 2005. The black box shows the size and location of the maps of Fig. 3, which have a smaller but more detailed FOV. A developed sunspot can be seen at the bottom right corner of the AR. Between July 2 and 3 the center of the AR was almost devoid of pores. On July 5 we increased the cadence of the sequence in order to show the quick appearance of new pores and orphan penumbrae at the PIL during that day.