What is the primary concern affected by parallax?

Parallax primarily affects sight alignment because it refers to the apparent shift in the position of an object when viewed from different angles. In the context of marksmanship, if your eye is not perfectly aligned with the sighting system (such as a scope), the target's position may appear to move relative to the reticle. This misalignment can result in inconsistent aiming, leading to shots that may not hit the intended target, even if the shooter is aiming directly at it.

Proper sight alignment is crucial for accuracy, as any discrepancy caused by parallax can lead to aiming errors. By ensuring that the eye is correctly aligned with the sight, shooters can minimize parallax error and improve their overall shooting performance. This understanding emphasizes the importance of correctly positioning oneself behind the rifle to ensure that the reticle and the target remain in line, thereby achieving a more accurate sight picture.