I went out with 2 friends and we all had our own yardage pro 1000. We set out to mark a 1,000 yard range for target shooting. Once again, the unit failed us. It was not a particularly sunny day or overly hazy but not one of our 3 units would even come close to ranging out past 650 yards. Under ideal conditions, one time, mine actually ranged a barn over a thousand yards. Today, I pointed at a huge oak tree with about a 4 foot trunk that was about 800 yards away. No reading at all, same for my buddies. These units seem to be accurate when working but to get past 600 yards, the conditions have to be perfect. We are all disapointed in ours.