these look like they are in the window of harvest if not very soon. In the pics it looks like the older trichomes in the interior of the bud are starting to amber, and it looks like over half your trichomes are cloudy. Make sure you understand that it isn't a percentage of amber you are looking for, its really an attempt to harvest when as many trichomes are fully developed as possible (indicated by the cloudy appearance).
In other words, wait til a bit more of the clear trichomes develop fully. After that you can let it go longer (where more CBN is produced). CBN gives more of a couchlock, but it is technically a degraded trichome. So for more medicinally beneficial cannabis which is what many people want, it is best to harvest with the highest percentage of cloudy possible (fully developed trichomes)... the science on the subject is somewhat divided and changing, and they are finding benefits to CBN as well if you are interested in that.
Sorry for rambling had a nice hit of 22 Jack before this... hope i helped.