EOTech Holographic Sight Parallax Induced POA Error Compared to Reflex Red Dot Sights

[Convex]

I think a reasonable measured estimate can be obtained without complex apparatus.

How in the fuck do you measure an estimate. If you have the ability to measure something, then it's no longer a "rough calculation" or a guess.

That's nonsense.


If you come up w/a precise measurement, you've left an "estimate" in the rearview mirror.

 

[Milirad]

And here is the kicker, Parallax shift doesn't mean jack shit at CQB distances. Running around with an IR laser and dot/holo shooting people inside 25yards, mostly inside 10 yards, it doesn't matter. Virtually everyone cannot even shoot offhand inside of the shift.

Right, but it does if you need to shoot unmagnified at 150-200 yards which is not at all an unimportant circumstance. We've been practicing at that distance and that is why I considered going to a holo sight, thought it would have less parallax. Instead I learned that regardless of holo or reflex it's just as important to train keeping the dot pretty much dead center. FWIW I looked for data on all this and the only thing I found with real measurements was the link I posted way up in this thread which runs contrary to my testing so I thought the data is interesting. Also, pretty much all the guys I talked to, including the teams at two local gun stores, said a holo sight would have way less parallax error than a reflex sight.

If you have some good references from the "mountain of proven tests" you talk about, if you don't mind sharing that it would be helpful.

Also, sorry you don't like the content, but there is lots of other things to read on the Hide. I have heard from some others this is helpful, although they are a bit intimidated by the hazing. Wish someone else had posted this kind of result so I didn't need to spend the time to take the data.

 

[Milirad]

How in the fuck do you measure an estimate. If you have the ability to measure something, then it's no longer a "rough calculation" or a guess.

That's nonsense.


If you come up w/a precise measurement, you've left an "estimate" in the rearview mirror.

No measurement is perfect. An imperfect measurement can be referred to as an estimate. An estimate of a performance parameter is far better than knowing nothing about the performance parameter. The more resolution one attempts to characterize in a performance parameter test, such as the difference in parallax error sensitivity vs eye movement in different regions across a red dot sight, the more difficult it becomes to be accurate. If there is a 10% difference in performance in the middle vs the edges, the testing methods used here is not accurate enough to determine that. However, if there is a 2x or 3x difference in the error in the middle vs the edge, that will definitely be evident in the test results, which are referred to as estimates since they are not perfect.

I love the shooting sports and love learning about optics, especially when it translates to better shooting effectiveness. I have been experiencing substantive errors at longer ranges when using red dots, so for me this is not an academic exercise, it is seeking improvement in real world situations. I'm also trying to figure out if it's possible to be pretty accurate with a red dot at longer range (say +/- 1 MOA), or if the inherent errors make it better just go with an LPVO. One can also run an SPR setup with MPVO and offset red dot. I have two such SPR 556 rifles which are good out to 600+ yards, but that adds about 2.5-3lbs depending on the scope, mount and red dot, which is a lot for a rifle primarily intended for CQB. It's all interesting to me, sorry if it isn't for you.

 

[Convex]

Love the way you can slip a "Straw man" into a discussion



straw man

[ˈstrô ˌman, ˈsträ ˌman]

noun

an intentionally misrepresented proposition that is set up because it is easier to defeat than an opponent's real argument:

"her familiar procedure of creating a straw man by exaggerating their approach" · "you are constructing a straw man argument"



Your "Straw Man" is your suggestion/inference that perfection was ever an issue when nobody mentioned it except you in your response.

To be precise has never meant being perfect, and to most folks including me using a high degree of precision means to be as precise as possible like in out to how many decimal places.



"es·ti·mate

verb[ˈestəˌmāt]

1roughly calculate or judge the value, number, quantity, or extent of:

"the aim is to estimate the effects of macroeconomic policy on the economy" · "it is estimated that smoking causes 100,000 premature deaths every year"


If you grab some other dictionary definitions, they'll mention a "rough calculation" or a guess.



"pre·ci·sion

[prēˈsiZH(ə)n]

noun

precision (noun) · precisions (plural noun)

the quality, condition, or fact of being exact and accurate:

"the deal was planned and executed with military precision"

marked by or adapted for accuracy and exactness:

"a precision instrument"

technical

refinement in a measurement, calculation, or specification, especially as represented by the number of digits given. Compare with accuracy.

"a precision of six decimal figures" · "this has brought an unprecedented degree of precision to the business of dating rocks"


There's nothng anywhere in the above definitions mentioning perfection/including perfection/lacking perfection, only your "Straw Men" you've resorted to several times in these discussions, and it doesn't change my point because I never mentioned perfection.



Nobody can "measure" an estimate, nobody talks about perfection, that's all there is to it".


I'd suggest disciplined minds try to be precise as possible, not perfect, and if you don't agree w/that then you're "full of it".


There's nothing you will ever do, say, or calculate that will be perfect, that doesn't exist when it comes to human beings.




Now..... I'll tell you what he's going to do, he'll read this and then type 2 pages about resolution.

 

[Rio Precision Gunworks]

No measurement is perfect. An imperfect measurement can be referred to as an estimate. An estimate of a performance parameter is far better than knowing nothing about the performance parameter. The more resolution one attempts to characterize in a performance parameter test, such as the difference in parallax error sensitivity vs eye movement in different regions across a red dot sight, the more difficult it becomes to be accurate. If there is a 10% difference in performance in the middle vs the edges, the testing methods used here is not accurate enough to determine that. However, if there is a 2x or 3x difference in the error in the middle vs the edge, that will definitely be evident in the test results, which are referred to as estimates since they are not perfect.

I love the shooting sports and love learning about optics, especially when it translates to better shooting effectiveness. I have been experiencing substantive errors at longer ranges when using red dots, so for me this is not an academic exercise, it is seeking improvement in real world situations. I'm also trying to figure out if it's possible to be pretty accurate with a red dot at longer range (say +/- 1 MOA), or if the inherent errors make it better just go with an LPVO. One can also run an SPR setup with MPVO and offset red dot. I have two such SPR 556 rifles which are good out to 600+ yards, but that adds about 2.5-3lbs depending on the scope, mount and red dot, which is a lot for a rifle primarily intended for CQB. It's all interesting to me, sorry if it isn't for you.

What distance and what size (angular and linear) errors? Also, what's the precision/dispersion of your rifle? What size targets are you attempting to engage?

Generally speaking, when you run a rig primarily for CQB/HR, you'll be running an RDS/Holo and Magnifier as you've pointed out. And the general idea is that when moving to distance measure in the hundred/s of yards and not feet anymore....you're not looking to take precision shots.

And the inverse is true. When you set up a "patrol" rifle, you'll be running an LPVO and possibly an offset or above optic RDS/Holo. With the purpose being more precise fire at the longer ranges and you're able to get by when you need it during CQB/HR distances.


Depending on the size target you are needing to engage, you may be expecting too much out of your RDS/Holo + Magnifier. Or may need to step the magnifier up to a 5 or 6x if you're using the typical 3x.

 

[Milirad]

Ok guys. Not sure what turns your crank, but I've had enough of it for now. Take care.

 

[Milirad]

What distance and what size (angular and linear) errors? Also, what's the precision/dispersion of your rifle? What size targets are you attempting to engage?

Generally speaking, when you run a rig primarily for CQB/HR, you'll be running an RDS/Holo and Magnifier as you've pointed out. And the general idea is that when moving to distance measure in the hundred/s of yards and not feet anymore....you're not looking to take precision shots.

And the inverse is true. When you set up a "patrol" rifle, you'll be running an LPVO and possibly an offset or above optic RDS/Holo. With the purpose being more precise fire at the longer ranges and you're able to get by when you need it during CQB/HR distances.


Depending on the size target you are needing to engage, you may be expecting too much out of your RDS/Holo + Magnifier. Or may need to step the magnifier up to a 5 or 6x if you're using the typical 3x.

Yes, that's the idea and your comments are helpful, thanks.

At 200 yards with a red dot I make more hits than misses on a small target from an improvised position when there is plenty of time per shot. But when I practice with position movement and faster shots I am considerably better with a scope than a red dot, even with the scope at 1x. This makes me wonder if I am not keeping the red dot close enough to the center of the window with time pressure and fatigue. With a scope there is no guessing about where the sight center is.

Running a scope on top, whether LPVO or MPVO, for longer engagement distance plus an offset reflex red dot removes the need for the red dot to be accurate. No need to mess with focus to quickly roll back and forth between CQ and distance, but it's heavy and bulky for a CQ rifle. This is a great setup but is pretty heavy and bulky.

LPVO alone is a descent alternative, but requires manipulation of magnification with the off hand, is still heavier than a red dot and sight acquisition for very close range, especially with movement, is considerably harder than with a red dot.

If you want a rig that is as light as possible with fastest CQ sight picture that's a red dot on top (holo or reflex), but It would be best to be able to reliably make hits at a reasonable distance. That's the scenario that requires a reasonable degree of accuracy from the red dot, meaning a reasonable parallax error. For a 200 yard shot on a 10" CoM target, if the parallax error is anywhere near what the EOTech website says to expect (as noted above), when you add shooter aiming error under time pressure and stress it's not a reliable setup. So the question I have now is just how close the dot must to be to the zero location to keep parallax error down to a reasonable level, say +/- 1MOA.