purple kush finishing time, help!

Hi this is my 2nd grow, my first was skunk #1 easy first grow, cut her down too early after being miss led on flowering time. Now i have 2 purple kush from marijuanaseeds.nl i have them in 7g drums 100% perlite hempys. Loving the hempy. Now with all my research people are saying 7-10 weeks.... i have a 30x 60x loop to look at the trichs but its pretty hard to keep it still long enough to actually see them. Is there anyone who has grown this strain this way that could shed some light. Their 4 weeks in from showing first flower.

Never grew it but its not like strains finish on an exact day. Environmental factors and phenotypes all play a role. Take a knee, hold the loop with two hands, rest it on your knee and look at a bud

Ok will give it a try thanks bud.