Before HT I had light brown hair on top. The sides and back were dark brown. After HT, the hair(transplanted) is a different shade from the existing. Does any one know if the color will blend in. Do I need some sun ?

The sun will definitely lighten it up a bit.
I have a similar issue with the hair on top slightly lighter. With me though, it really doesn't seem to be an issue.
On a side note, it'll be slightly interesting when I/we go grey if the transplanted hair will gray first, later on, or just "assume" the coloration characteristics of the hair around it.
Probably not the last option, but who knows.

vocor1
Knowledge is Power
If the worst question is the one never asked, then the worst answer is the one never shared.

East Coast,

I too have lighter hair on top than in the back where the donor hair is obtained...and right when it started growing in, it appeared a bit darker than the top/front, but like Vocor1 mentioned with time and some outdoors, it now blends in with the rest. It will most likely not be an issue.

NW

Vocor1,

My transplanted hairs seem to be graying about the same as the rest of the hair on my head. I have that salt and pepper look elsehwere and the same mix of brown and white hair in the minis and micros from my past HTs.

Mr. T