lack of trichome developement in upper buds

As the title says. I about to enter the 7th week of flower and its all going pretty good but one thing i have noticed is that the buds slightly lower down are much more frosty than the buds directly under the lights.

Is this normal? Or is it possible that my lights are too close? I do not have any of the classic light/heat stress symptoms

I believe it's entirely normal and possibly your light is a little to close but I have noticed in all of mine the very top buds seemed to be a little less trichey, but once dry it all seemed the same.

Type of light and wattage? How far away is the light from the top of the canopy? How long is the stated flowering stage of the strain you are growing?