I think in mid 1969 Topps reached a new agreement with the Players Association and it's new head Marvin Miller. An agreement much more favorable to the players. The result was new pictures started to show up in the latter series of cards, but at least the first 4 or 5 series had many recycled pictures. Expansion teams also had an impact that year. I think Olberman may have also done an article on 69 photos
http://www.sportscollectorsdigest.co...res/1969-topps