Target detection is a life long & constant learning skill. As detection distance increases the more the skill set has to be refined. We had guys that were excellent shots with subs to 5-600yds no matter what mother throw-ed at them but could not find a simple target at 1-200 yds. In that short of a distance even with a subsonic its almost a gimme, as the average shooter was well under 2 moa at that distance.
If you really what to learn, get a friend to start setting simple targets at unknown distances w/o camo and as you progress revert to smaller & different levels of camo. Once you're deep into it, start using the sun & moon angles to your advantage. No matter how good of a shot or tactician one is, if they are always reacting,... at some point their luck will run out.
Good static target detection skills don't happen overnight,... and like electricity, (and many other things) not being able to see the threat does not mean its not close enough to, tag you.
