Your not really supposed to harvest to signs of hair changeing. Yes when they turn orange its usually a late stage. Look with a magnifying glass to see the trichomes. They need to be at least 70% amber when you harvest. Seriously, if they are clear don't do it. if they are cloudy that means they are geting there and if they are amber/dark red/purple it means they are ready. I go 50/50 with cloudy and amber myself. It would give you a beter buzz too. If everything goes well i would say you'l harvest half and oz per plant at least dried. But maybe an oz per plant if you keep going well. Peace out