Vortex Optics CROSSFIRE II 4-16X50 AO RIFLESCOPE - Manual (Page 4)

Some of the Crossfire II riflescope models use an image focus/parallax
adjustment which provides maximum image sharpness and eliminates
parallax error. Lower power models do not use image focus/parallax
adjustments and are pre-focused at a distance of 100 yards.
Image Focus and Parallax Correction
• Be sure the reticle is correctly focused (see Reticle Focus on page 4).
• Rotate the adjustable objective until numbers match the distance you
are shooting. Align yardage number to the indicator arrow on scope body.
• Check for proper setting by looking through the scope to verify image
sharpness and, at the same time, look for reticle shift while moving
your head back and forth. The setting is correct if there is no apparent
movement between the reticle and target while your head is moving back
and forth. If there is apparent movement, adjust the focus knob slightly
until the movement is eliminated.
Using image focus/parallax correction:
When properly set, the target image should be sharp and crisp.
7 6
RIFLESCOPE
II
Parallax is a phenomenon that results when the target
image does not quite fall on the same optical plane as the
reticle within the scope. When the shooter’s eye is not
precisely centered in the eyepiece, there can be apparent
movement of the target in relation to the reticle, which
can cause a small shift in the point of aim. Parallax error
is most problematic for precision shooters using high
magnification.
Match shooting yardage to
indicator dot. 100 yard setting
shown.
Adjustable Objective
(AO models)
What is Parallax?