Why not join immediately?
You can check the winners of last round here:
https://peakd.com/hive-150329/@friendlymoose/winners-pobphotocontest-circles
Or all submissions here:
https://peakd.com/hive-150329/@friendlymoose/pob-photocontest-subject-circles
Thanks for the links. I will go through them and see what I can come up with for the contest.