Q. Scope instructions generally state that you should focus the eyepiece on the crosshairs. While this may show clear focus on a target at lower powers, at higher powers, the target’s image may get fuzzy on some scopes. Is there any solution, or is this limitation inherent to certain scopes?
A. Focusing the eyepiece of a scope sight is solely intended to control the clarity with which you see the reticle. The sharpness with which you see the target is determined by a variety of factors, including the target distance relative to the distance for which the scope was focused at the factory, as well as the distance for which you have set the focus of a scope that provides user-adjustable objective focusing. Target sharpness is also affected by atmospheric conditions, lighting, the scope’s overall optical quality and the condition of exposed optical surfaces (clean vs. dirty; scratched vs. pristine). Other factors can also affect target clarity to varying degrees.
-Hugh C. Birnbaum
Originally published May, 2006