Astigmatism & Dot Size

[iron_road]

Not sure if there is much credence to this. But one thing I have been hearing for people with folks with astigmatisms such as myself that red dots tend not to smear as much or not at all when equipped with a higher MOA dot. For example a 2.5 MOA dot on the mid setting would look like it is smeared or giving the starburst effect opposed a 5 or a 6 MOA dot. I can't say for certain that has been my experience as I have not owned reflex sight larger than 3.25 MOA. What has everyone else's experiences been especially if you have an astigmatism?

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[po18guy]

Astigmatism here. However, I had cataracts removed and engineered multi-focal lenses implanted. Except for a halo effect/spider-webbing around light sources at night, it was a win-win. Red dots are much better now.

 

[JRCX17]

You pose an interesting question, and I have some thoughts as someone who looks at optics all day long. I personally say that yes, the larger the dot, the less you notice any Starburst or streaking. The thing about astigmatism is that everyone has it to a degree. Nobody's eyes are perfect and astigmatism has to do with how well light is passing through one's eyes. The worse in deviation in the shape of one's cornea or lens, the worse the astigmatism will appear. I think what lends to the larger dots being better is that I don't feel like I have to have the brightness turned up as high to see the dot clearly. The higher you have your brightness up the more intense the Starburst effect is. Since 3moa dots are actually pretty small I think most people feel the need to have the brightness cranked so they can see it well enough, but then it ruins the dot clarity. It also has some to do with the choice of emitter that a manufacturer uses. Some are better than others and just produce a crisper dot from what I have seen. Also if you're talking rifle red dots and then put a magnifier behind it, the size of the dot increases, but then so does the perceived brightness. So a dot might look fine unmagnified, and then be a blurry mess when looking through magnification. Another thing I find helps is circle dot reticles. I think this has to do with the emitters used, but also the fact that the circle makes everything easier to pick up and focus on. So something like the Holosun 507 series or Sig Romeo-X might be something to look at too, for handguns at least. All that said. As someone who has been in the 3moa camp for a long time, after looking through different 6moa optics, I've decided to make the switch. If nothing else get your hands on a demo or two and check out the options.

 

[Yarome]

Comparing 2 fastfire III's side by side... one 3moa and one 8moa. The 8moa definitely has a much larger flare. For me at least, the larger and brighter the light, the larger the flare. The only exception was each on the lowest intensity setting. Both the 3 and 8 were both about equally crisp, but the 3moa was definitely more difficult to pick up.

So... for equal ease of visibility, I would prefer the 3moa at medium intensity and the 8moa is just perfect on the lowest intensity. The result... the 8moa appears fairly crisp/clear and the 3moa has a noticeable flare.

That seems to jive with @JRCX17 's intensity theory over actual MOA size that people may be reporting. Anything other than the lowest intensity with the 8moa has a massively larger flare/starburst than the 3moa at equal intensities, so... needless to say... I prefer the 3moa.

 

[Joe13]

If I don't wear my glasses the dots look like a heart beat monitor, which is totally impractical for shooting. With them in the dot is crisp and clean.

I don't really need them for anything else in life that I do though.

 

[Member 24198]

I gave up trying to get a dot to work. I run traditional scopes or etched reticles.

 

[Stomper]

Through my right eye, both of my Aimpoints' 3MOA red-dot has a little "flare/tail" at about the 2:30 position on the brighter settings, but running it on the lower (yet still easily visible) settings mitigates it.

 

[JRCX17]

Comparing 2 fastfire III's side by side... one 3moa and one 8moa. The 8moa definitely has a much larger flare. For me at least, the larger and brighter the light, the larger the flare. The only exception was each on the lowest intensity setting. Both the 3 and 8 were both about equally crisp, but the 3moa was definitely more difficult to pick up.

So... for equal ease of visibility, I would prefer the 3moa at medium intensity and the 8moa is just perfect on the lowest intensity. The result... the 8moa appears fairly crisp/clear and the 3moa has a noticeable flare.

That seems to jive with @JRCX17 's intensity theory over actual MOA size that people may be reporting. Anything other than the lowest intensity with the 8moa has a massively larger flare/starburst than the 3moa at equal intensities, so... needless to say... I prefer the 3moa.

Yeah that makes sense. I would definitely guess there are diminishing returns once you get to those really large dots. But I haven't actually had a chance to look through one. The other thing for everyone to keep in mind is ambient lighting. The darker of an environment you're in the lower you're brightness will need to be, which is kind of a given, but I feel needs to be said sometimes. If you were to do this same experiment outside in the sunlight I'd be curious to see if you get the same results. I guess one more thing to look for is a dot with a wider range of brightness levels for fine tuning since that would give a better shooting experience. But it does depend on your use case or purpose for the firearm and optic as well. Range gun, EDC, etc. Thanks for the insight Yarome.

 

[Nosferatu]

I just use the center-ish of the blob, no matter what size it's supposed to be.

 

[VinnieBoomBah]

I just use the center-ish of the blob, no matter what size it's supposed to be.

Same here. All the usual JMHO and YMMV and all that, but for what I use a dot for "putting the blob on the part I want the hole in" works just fine. If I need more precision than that I use something other than a dot

 

[JRCX17]

Same here. All the usual JMHO and YMMV and all that, but for what I use a dot for "putting the blob on the part I want the hole in" works just fine. If I need more precision than that I use something other than a dot

I also find this to be a solid methodology

 

[iron_road]

For context purposes this is for EDC on a pistol platform so this might change the dynamic a bit.

 

[JRCX17]

For context purposes this is for EDC on a pistol platform so this might change the dynamic a bit.

I'd at least check out a 6moa dot. It's not like you're planing on using an edc to shoot very far or thread needles. At least for most instances. I like to see fast so I can shoot fast. Bigger dot helps me do that.

 

[VinnieBoomBah]

For context purposes this is for EDC on a pistol platform so this might change the dynamic a bit.

Not for me, that's exactly what mine is for. Back in the days of my youth I was pretty good with my 1911, not particularly fast but I could hit a silhouette target at 100 yards most times out of a magazine These days I'm lucky to see it with iron sites.
I am a better, faster, more accurate shooter even without my glasses if I'm using a pistol with a red dot then I ever was with iron sites.
The trick is to make sure that whatever pistol dot combination you use they come up to your natural point of aim so you don't have to go hunting for the dot every time.
The recommendation I saw a couple different places was to take whatever pistol you normally carry with iron sights and in a safe environment, close your eyes and draw and open your eyes. If the sites are where they're supposed to be a red dot will probably work good for you, but if you need to move things around after you open your eyes to get the sites lined up, you will probably have problems with the red dot on that pistol

 

[iron_road]

In which case that sparks another question in my mind Trijicon 5MOA SRO vs 6.5MOA RMR? In essence Wider window vs Smaller Window?

Now I've had both. I currently still have my SRO in 2.5 MOA. And I am certain about trading for either a 5MOA SRO or a 6.5MOA RMR. But what drove me away from my old RMR that was in 3.25 MOA was how small the RMR window was in the first place. But I am thinking if the dot is bigger that maybe the small window won't be a problem.

However what worries me about the SRO's design to take a blow if dropped. Not that I am abusive to my optics, I am just saying bubblegum happens. However Trijicon is no slouch and builds their stuff rugged so it should be relatively tough no?

 

[Paolung]

Not sure if there is much credence to this. But one thing I have been hearing for people with folks with astigmatisms such as myself that red dots tend not to smear as much or not at all when equipped with a higher MOA dot. For example a 2.5 MOA dot on the mid setting would look like it is smeared or giving the starburst effect opposed a 5 or a 6 MOA dot. I can't say for certain that has been my experience as I have not owned reflex sight larger than 3.25 MOA. What has everyone else's experiences been especially if you have an astigmatismMy astigmatism has been compensated for by LASIK now, but when I it still bothered me. I had luck with some of the Holosun dots. I don't recall size of the dot mattering as much.

My astigmatism has been compensated for by LASIK now (no complaints!), but when it still bothered me, I had luck with some of the Holosun dots. I don't recall size of the dot mattering as much.

 

[VinnieBoomBah]

I also like the Holosun, I run a 2moa 507K on my Shield

This is a pretty good video on the subject

View: https://www.youtube.com/watch?v=efaGYhIi3Sc

 

[po18guy]

I gave up trying to get a dot to work. I run traditional scopes or etched reticles.

Old.
School.
Note: it is, however, a certified school.

 

[Benchrest]

Edit: I recommended a prism when the OP is asking about pistol RDs, I'm an idiot

 

[WillametteWill]

Large 32 moa Holosun green circle for the win with my astigmatism. Personally, I have found that different brands seem to make l bigger difference. I'm betting this is personal depending on our eyes. Without my glasses, they all suck, just some less so. With glasses, some are pretty good. Green helps me as do Holosun and Crimson Trace...don't know why. Burris is not too bad. RMRs and Delta Point Pros do not work well for me...too bad since they are great optics.

But the easy fix, for me, is the 32 moa circle in the green Holosuns (508T-GR) with no dot in the center.