I had a terrible time in my last grow waiting for the trichomes to turn amber...

I think I was on week 13 when I finally say some amber. I was growing Big Bud x Northern Light.

I think the main reason for the lack of amber trichomes was because I am an LED grower.

After chatting with some other LED growers I finally came to the conclusion that the LED wasn't producing enough UV light.

Perhaps the trichomes are affected by the UV created by the sun and even HPS lighting. My LED does have one UV and one IR diode in the lamp.

Maybe the combination of the heat produced by the conventional HPS lighting might also be a factor. Might be interesting to find out from T5 growers how trichomes react to fluorescent..

Or possibly purely CFL growers...

My buds were left too long as they started to get deformed from extra growths growing out the side of them. Still got me more bud though

Anyway, hope this might help others to share their experiences with different lighting.

BamaGrower is 100% right about the microscope. I have one too, got it for $4 on eBay. I even invested in a USB microscope so now I can take photos on my laptop.

Take Care dude

S.L.