Parallax...what is it

[FirstBMW]

I am looking at a extended eye relief scope for a scout mount on a M44.
The details on the EER scopes say stuff like, " parallax set to 100 yards".

What does that mean to me? Is that good or bad?

I should stick to Ironsights, at least I know how to work them.....

Thanks for your help

 

[prosper]

Hold two finders out, in fromt of your face. Now, wihout moving your fingers, move your head side to side. Notice how the far finger seems to move in relation to the close one? That's parallax, only with a scope it's not fingers, it the reticle and the target.

Depending how a scope is focused can eliminate parallax, but only at a specific range. Therefore, fixed-focus scoped are usually set to be parallax-free at 100-ish (sometimes 200) yards.

Regardless how the parallax is set, there will not be any parallax error if you're form is perfect and your line-of-sight is exactly 90* through the glass. And even if it's not, parallax error should only account for fractions of an inch out to 200 or so with that scope.

 

[trubluscrew]

http://www.usoptics.com/sub_pages/parallax.php

 

[FirstBMW]

Very helpfull.
Thanks both of you.