I assume this plant as week6/7 am i right?

if you want to guess based on when it went into flower.. figure 7-10 days before you saw preflowers formed. This won't inform much about harvest date unless it's a clone you are familiar with. once the calyxes are fully plump, start scoping trichomes. How much amber do you wantt? this is a personal preference you will need to learn. When you see it reach that preferred threshold, go ahead and harvest the plant. Easy-peasy. The closeups are fine, but if the calyxes aren't fully plump you don't have to scope the trichomes yet. they'll send contradicting signals if you look too early. Trichomes are aging and turning amber at various points all over the plant long before harvest time.