It's really hard for me to tell from your pictures, but the trichomes at first will look clear, like tiny rain drops. As the plant matures, the trichomes will look cloudy, so that you can not see through them. Some strains, the trichomes turn amber rather than cloudy.
If you can get a hold of a 30x Jeweler's loupe, you will be able to see them more clearly. I got mine off of eBay for $6.00.
You said your plants are into 9 weeks of flowering. Give it another week and look at the difference between then and now. You will see the trichs turn color. Good luck with your harvest!