Voltage Drop in PV Systems: Page 2 of 3 | SolarPro Magazine
Found this to be kinda helpful.
Seems for a long haul emt will be the most reliable .
Still so far i have not found squat on what i am trying to find out on how i need to run my dc from the last optomizer to the spot where i am going to go off of the roof . My only guess is under the panel just put the wire through it and mount the emt a little bit off the roof so it dont touch and hold trash.