Can an aperture rear sight with a -.5 diopter corrective lens have parallax problems?I believe parallax is an issue unique to optics, and does not occur with open or aperature sights that utilize no optical elements.
If used properly, metallic sights always appear the same relative to each other and the target. I'm not sure what this question means.Does a barrel aimed with metallic sights always point to the same place on target regardless of how they may appear relative to each other and the target?
If front sight center is to the right of LOS upon firing, shot will go right.
If rear sight center is to the right of LOS when fired, shot will go left.
Yes, I erred. Corrected the post. Thanks. Sometimes hard for me to explain. It's complicated.If either of those are true then the sights are not zeroed. I don't see that as a parallax problem.
It's equal both ways. I've observed this a few times shooting 4 man team matches with the same rifle and ammo.Another shooter may hold the rifle differently and a rifle zeroed for me may not impact in the same spot as someone else. And I see this as more of an issue with iron sights than optics.
Strictly speaking, that's sight misalignment.Parallax with metallic sights exists when front and/or rear sight center is not on the line of sight between eye and target center.
I have demonstrated my reasoning is factual with a rifle hard mounted in place aimed at a target then moving front and rear sights so people can see what happens.Strictly speaking, that's sight misalignment.
Parallax exists when the sight(s) appear to be properly aligned with the target but aren't because the shooter's eye is not properly aligned with the sight(s). That can't really happen with metallic sights.
Bart B. said:I have demonstrated my reasoning is factual with a rifle hard mounted in place aimed at a target then moving front and rear sights so people can see what happens.
Yes.Is parallax eliminated the same way with both metallic and optical sights?
That's a parallax situation, not a parallax error. The parallax error is how far bullet misses point of aim when a parallax situation exists.If I do the same with an iron sight rifle (move my head while the rifle is stationary), the front post and target move off center, so I no longer have what appears to be an aligned sight. That's not a parallax error because it isn't an error, but the iron sights doing what they are designed to do -- tell you when the back and front are or are not aligned to a spot on the target.
I don't disagree with your explanation of what happens when the sights are misaligned as you describe. I just don't think it fits the definition of "parallax".I have demonstrated my reasoning is factual with a rifle hard mounted in place aimed at a target then moving front and rear sights so people can see what happens.
I agree 100% with that definition of parallax.We first must agree on what parallax is defined as by some standard; perhaps a dictionary?
There is no defined "point of aim" when the eye is out of line with metallic sights or when the metallic sights are misaligned with each other. The only way to see the point of aim is for the sights to be aligned with each other and with the eye and there's no parallax when that is the case.The parallax error is how far bullet misses point of aim when a parallax situation exists.
Therefore, it is impossible to call a shot when that happens and the bullet may not hit the 6 foot square target paper 200 yards away. There is no way to tell where the front sight appeared relative to the bullseye when a shot is firedMoving the eye off axis in a metallic sight system effectively "destroys" the aiming point so there is no longer any apparent aiming point at all.
Bart B. said:Therefore, it is impossible to call a shot when that happens and the bullet may not hit the 6 foot square target paper 200 yards away. There is no way to tell where the front sight appeared relative to the bullseye when a shot is fired
Right?
Both iron and scope sights have parallax problems when aim point on target, sight reference points and aiming eye are not on the same axis. Doesn't matter how far apart they are.Calling a shot is a matter of prediction and judgement, not a merely physical phenomenon.
While parallax can be observed when any two objects are at different distances, misalignment of iron sights isn't the same phenomenon as parallax evident in an optic at a given distance. The ideal on an optic is to have everything focused on the same plane. Since that can't ever happen on iron sights, parallax can't be eliminated the same way. On one parallax is a simple alignment problem; on the other its a focal plane issue.
One can remedy or reduce parallax error in an optic with the use of an aperture that demand better alignment, but since greater flexibility and ease of use are part of the advantage of an optic, that's not a very popular remedy.