Azimuth is needed in elr due to the coriolis effect. Like if your shooting north in Canada as the earth spins your projectile windage will be compensated for in the kestrel. Or shooting west at the equator it will not be much deviation. The kestrel also needs to have your latitude so it can compute these things. Not needed at all anything less than 1k unless your for some reason shooting long range with subsonic ammo. It’s all about how long your projectile is in the air as the earth spins.