But it's all a matter of individual taste. Only
you can say when the bud is where you want it to be for whatever reason (couchlock, headhigh, etc).
There is no "magical" time to harvest every strain for every toker. Some folks harvest when the trichomes are 80/20 cloudy/amber...Some like no amber at all. Some like clear and cloudy, and it all changes depending on the strain as well.
That's why the question of "when to harvest" can only be answered by the individual that is going to be smoking the bud and
imho the easiest and quickest way to find that out is to quick dry a sample, whether the quick dry is done by oven, microwave (yuck, but my personal opinion), food dehydrator or setting it on top of your computer monitor.