finestanswered grow question a year ago look at the trichomes - if you don't have microscope make a macro photo and zoom, personally I take different routes...
1- when most of the trichomes are milky/cloudy - for peak THC/ nice head-high
2- when most of the trichomes got amber - more CBN /more sedative effect,
If you are making oil, wait for the amber colors 😋
All depebds on the strain and desired effect. Good luck.