Easy test for astigmatism with RDS

[0reo]

Take a small piece of paper & punch a tiny hole (≈1mm) in it with a pen. Look at RDS reticule through hole in paper. See the difference?

I was reading a bunch of old threads here & came across a few that described how an astigmatism makes the nicely shaped dot of an Aimpoint look like a comma, or a star, or fuzzy. I then remembered a bit of my photography lessons about the effect of aperture size on focus. So I tried the hole-in-paper trick & holy-moley, what a difference! Apparently I have an astigmatism. Never realized the Aimpoint dot is that crisp but it really is nice if you've got the eyes to see it with.

[Doc Safari]

I played with various optics at a gun shop for a couple of hours one afternoon. It was an eye-opening experience (pun intended). I prefer the ACOG reticles, but their eye relief sucks.

I too have astigmatism and I have some issues with red dots. I can use red dots on the lower settings and the dot doesn't "star" too badly, but on higher settings the dot definitely looks like a flame.

The EoTech reticle always looks "fuzzy" to me like it's made of yarn or something. The Aimpoint reticles aren't too bad on lower settings as I said, and I think for the most part I can use them.

If you have astigmatism, or even suspect you have it, I would strongly recommend you try out some red dot sights in a gun shop before you buy one. I definitely suggest you do not blindly order one over the internet if you think you might have issues with astigmatism.

[militarymoron]

the same thing can be observed by looking through the small aperture of the rear iron sight while looking at the dot.

[0reo]

I had no idea I had an astigmatism till I got my T1 the other day. The dot isn't too bad for me but I can definitely see the difference looking through a pin-hole. Makes me wonder how much corrective glasses would improve the rest of my vision.

[Zzzake]

Very cool test, the dot is all of sudden perfectly rounded and crisp. I also found that if you look through a magnifier at the dot, it also sharpen things up quite a bit.

[Skang]

I had to return my T-1 next say, because all I saw was red glowing tangled worm inside glass.

[tommyrott]

if you wear glasses and haven't updated your prescription for a while get your eyes checked, used to be the Eo-tech looked fuzzy and larger , now with an updated distant script its nice and crisp even on highest setting, and also Acog, h1 reticles also look nice and clean no fuzziness at all

[LHS]

Very cool test, the dot is all of sudden perfectly rounded and crisp. I also found that if you look through a magnifier at the dot, it also sharpen things up quite a bit.

I had just the opposite. The dot was always slightly fuzzy, but when I added an Aimpoint 3x, it turned into a three-way dot, kind of a glowing red Mickey Mouse silhouette.

[bp7178]

ACOGs and the TR24s always looked very crisp. I think the illumination being fiber optic has a big part in that.

Even the dot on a S&B distorts slightly, but no where near as bad an Eotech. The Eotech reticle looks the worse.

When used with a magnifier, the Eotech reticle looks better, closer to the drawings/pictures. The Aimpoint/magnifier combo was better than no magnifier, but not as big of an improvement as with the Eotech.

If I had any money I would create some type of add on lens system, something that could be concealed in a scope cap or the like, which would correct minor uncorrected astigmatism.

Lenses which correct astigmatism are cylindrical. This is why on a Rx you get numbers like -2.25 -1.00 135.

The first number if negative, corrects myopia, nearsightedness. The second corrects astigmatism, and the third is the axis of the cylindrical lens. All of these numbers, except axis, are expressed in diopters (a lenswith a power of one diopter has a focal length of one meter).

Rifle scopes already have a diopter correction, but nothing for astigmatism, or any uncorrected astigmatism.

Think of how much eye strain you could get rid of with magnified optics. You could even coat the lens with anti-reflective material, like high quality lenses in a scope should be.

I may have to look into this and file a utility patent.... ; )