that is why I carry a range finder so I can check out different objects and judge yardages from there. But it never fails last year a doe was standing 25 yards in a spot that I haden't used my rangefinder and I guessed her for 30 and it went over her back, but luckily she came back to a spot that I knew was 17 and she tasted great.
As Caliper said on a 3D range we do fine but on a 3D range we are not 20 feet in the air and most 3D targets are smaller than real animals

good luck and God bless