Hi. This is going to be my first year hunting whitetail with a bow. For the past couple of months I've been practicing daily on a range that I set up in my yard. I shoot 10,20 & 30 yds on a flat surface, 10, 20 & 30 from my deck, and 10, 20, 30 from my roof approx 12-15 feet off the ground. From all three shooting areas I notice very little difference in adjusting my aiming or shot placement. My question.....from my stand, how do I actually measure shot distance - from the base of the tree or from the stand itself & my stand is about 20 ft up. How will this affect my choice of pins?? Any help would be greatly appreciated.