You need a 30x jewelers loupe to see the trichomes and judge when to harvest. Most people harvest from 5%-30% amber trichomes. Harvest at 5%-15% amber trichomes for a "head high" energetic effect and harvest at 30%-50% amber trichomes for a "body stone" sedative effect strain dependent.
Here is the 30x jewellers loupe I own
https://www.sunflowersupplies.com JEWELERS LOUPE 30X MAGNIFICATION LED LIGHT 21mm LENS
If you do not have a jewelers loupe and wish to go by how many pistils have withered, wait until 85% of the pistils have withered to harvest.
Here is the 30x jewellers loupe I own
https://www.sunflowersupplies.com JEWELERS LOUPE 30X MAGNIFICATION LED LIGHT 21mm LENS
If you do not have a jewelers loupe and wish to go by how many pistils have withered, wait until 85% of the pistils have withered to harvest.