Small shift of Eotech POA?

[marksmatter]

My wife was good enough to buy me an Eotech 516 for Christmas. It arrived today, and just like any responsible consumer, I felt compelled to ummm...check it for quality.

I turned it on and placed it on a stable surface. I was particularly interested in the fact that the POA (and 1 MOA dot) should remain the same regardless of where in the glass you were viewing the reticle.

I was a bit surprised to see that as I moved my head around, the POA seemed to shift slightly. My "target" was the label on a bottle about 10 - 12' away. When viewing the target and reticle on the extreme left side of the lens, I would estimate that the POA moved about 1 - 1.5" as I shifted my head to view everything from the extreme right side of the lens.

Is that normal? Am I just being too picky, or am I misunderstanding something?

I should add that there is nothing about this sight that would indicate it is anything less than genuine Eotech. That was one of the first things I checked out.

[rebelEMPIRE]

Point of Aim should be Point of Impact. Try tracking something at a farther distance (25 meters). Where exactly did your wife buy the EOTech? And it isn't Christmas yet, by the way. =P

There are a lot of fake EOTech optics out there that are nearly indistinguishable from the real thing. I would contact L3 Communications if you have any bit of doubt in the authenticity of your product.

-rebelEMPIRE

[marksmatter]

The EOTech was purchased on eBay but from a seller with a real store - poorfish.com. The site is operated by MSO Outdoors. EBay had the best price bar none that I could find (about $380 before $50 rebate). Yeah....I know I have to give it back to her to have it wrapped. :(

According to EOTech's page at http://www.eotech-inc.com/documents/Recognizing%20counterfeit%20EOTech%20Sights%204-09.pdf, this sight passes all "tests", so I'm pretty sure it is legit.

I think your suggestion on distance has merit. If you block the front of the lens with your palm, the reticle clearly moves across your skin (i.e. at that close distance, theroetical POA no longer equals POI). Therefore, I would surmise that this "error" diminishes, but does not completely disappear at 10-12'. I am hoping to see that at 25m, it is negligible.

More soon.

[Paulo_Santos]

Aimpoints, EOTechs, and other red dot sights are parallax free. He reticle will move around if you move your head. That is the way they are designed.

[marksmatter]

I just received a response from EOTech.

I asked:
At what target distance does point of aim equal point of impact when looking through the lens? The closer a target is (for arguments sake - say the target is one inch away from the front lens) the more the point of impact appears to change as the user's head is moved. I am sure this characteristic diminishes with distance, but would like to determine what that is.

They responded:
At 30 yd this condition of parallax will diminish and be completely gone at 100 yd. At very close distances it is visible but does not affect the ability to hit the target at close range.

So, there is some close-range parallax error, but it quickly diminishes. However, that was what I was seeing during my indoor testing last night.

All is good again with the universe! [:D]

[Paulo_Santos]

IIRC, Aimpoints are supposed to be completely parallax free after 50 yards.

On our EOTechs at work, even up close, I never really noticed any parallax error.

[marksmatter]

The difference in our observations is probably due to the fact that I was specifically looking for it. That said, the magnitude of the "shift" is approximately 1" - not much to be concerned about at those ranges, given that it diminishes with distance. Initially, I was more concerned with ensuring I did not receive an imitation EOTech.

Appreciate the input from you and rebelEMPIRE.