How should corrective lenses to setup for Optimum Scope Use?

[hoz53]

I know how the eye focuses on one thing at a time. When we are young it may seem like we can focus on more than one thing at a time but we cant, young eyes can just focus back and forth that fast and good. So if we need corrective lenses the eye doctor can set them to focus at one optimum distance. Sure the eye can focus on more than one distance with our corrective lenses just not as good as the optimum distance. Some shooters get corrective lenses set to focus on where the sight is they want to focus on. this can help alot if a shooter is using irons. But how about the scope? Where should the eye be set to focus or how should correction be set up ? I know scopes have a focus adjustment to adjust for this but that only goes so far. For some people not far enough. Any info would be appreciated. I will ask an Eye Dr soon also and report here. Thank You

 

[kindabitey]

A combination of being old as dirt, and a life long welder puts me in the same boat. So far, I've had the best results with mono-vision contacts. It did take a while to find an optometrist
who had any interest in fixing my issues with a scope/ binos. Find someone who will sit and listen, instead of running as many folks through the office as possible.

 

[Forum Boss]

With magnified optics you are actually looking at a small circle of light (the "exit pupil”) a few inches from the back of the lens. So you want to set your correction to see something fairly close to your eyeball.

FWIW, I have perfect close vision, but use contacts to better see distance. I can shoot best with NO contact lens in my right eye, the one that looks through the lens.

 

[jackieschmidt]

10 years ago, I had Lasix done on my eyes. They gave me a far away eye, and a close up eye. I never thought to question which one, but the left eye turned out to be my close up eye. For years I have looked through my scope with both eyes, watching the conditions. After that, I had to move my head a little more to see my flags over the scope. Being a heads up shooter, it wasn’t that big of a deal.

Now that I am 73, I have developed a small cataract in my left eye. Sometimes it is a real problem, other times not. To read, I bought a set of cheap readers at +325, which makes the right far away eye the same as the left close up eye.

I am goin to get multifocal lens replacements next year. However, I was told since I had Lasix, They can give me great far away sight but I will have to us readers. They went all into why, (they don’t tell you this when hey do the Lasix), something about how they recurve the cornea and it screws up the programming for the new lens.

But I did enjoy great vision without glasses for 10 years

 

[hoz53]

A combination of being old as dirt, and a life long welder puts me in the same boat. So far, I've had the best results with mono-vision contacts. It did take a while to find an optometrist
who had any interest in fixing my issues with a scope/ binos. Find someone who will sit and listen, instead of running as many folks through the office as possible.

Thanks for this info. I asked the oprometrist today and didnt get much response. Ill be going back soon, so I will find out more.

 

[hoz53]

With magnified optics your are actually looking at a small circle of light (the "exit" pupil), a few inches from the back of the lens. So you want to set your correction to see something fairly close to your eyeball.

FWIW, I have perfect close vision, but use contacts to better see distance. I can shoot best with NO contact lens in my right eye, the one that looks through the lens.

Now that is really good info about the exit pupil and focus and what I needed so i can talk with the eye Dr. All these years Ive known about exit pupil i should have figured that out. I was near sighted all my life and had good near vision to, but i had cataract surgery a few years ago and i have distance lenses from that so I need to use readers to see up close. I do have damage to my right cornea also. So with all this stuff dont know what would really be best but ill be asking the eye docs. Thanks

 

[hoz53]

10 years ago, I had Lasix done on my eyes. They gave me a far away eye, and a close up eye. I never thought to question which one, but the left eye turned out to be my close up eye. For years I have looked through my scope with both eyes, watching the conditions. After that, I had to move my head a little more to see my flags over the scope. Being a heads up shooter, it wasn’t that big of a deal.

Now that I am 73, I have developed a small cataract in my left eye. Sometimes it is a real problem, other times not. To read, I bought a set of cheap readers at +325, which makes the right far away eye the same as the left close up eye.

I am goin to get multifocal lens replacements next year. However, I was told since I had Lasix, They can give me great far away sight but I will have to us readers. They went all into why, (they on’t tell you this when hey do the Lasix), something about how they recurve the cornea and it screws up the programming for the new lens.

But I did enjoy great vision without glasses for 10 years

Im 63 and have been very near sighted since 4th grade or before. Wore contacts since i was 16. Coke bottle glasses before that. I had cataract surgery 6 or 7 years ago and at that time had distance lenses put in both eyes, so i have to use readers for reading and up close. I decided not to get the multifocal lenses as they didnt recommend them for me. For the additional cost i would have still had to have eye correction. So during the cataract surgery also had lasix (i think) done on my left eye also so i wouldnt have to wear corrective lenses for it. Couldnt do that on my right eye (dominant eye) because i have kerataconus in it which means the cornea has flat spots on it. The cataract surgery was like a miracle though the way it corrected my vision. I couldnt read speed limit signs along the road before it. So My left eye works great for sighting through the scope but my right eye not so much. even with a contact in it the dot bounces around and sometimes i see 2 dots. When i shoot pistol irons i align the sights with my left eye and it works pretty good. trying to shoot off a bench though with left eye seems very awkward. Reader glasses when using my right eye for scope or irons seem to help alot to. I dont know if I could look through the scope with both eyes like you have done. Now I know you have though ill try it more and mabie ill develop that ability. If you will have to have readers for close up with the multifocal cataract lens, i wonder why you wouldnt be just as well off with distance lens. i wonder if youll have to use the readers all the time sighting through the scope? Another thing they didnt tell me would happen is the cataract surgery caused me to have many many floaters. Big ones to. They havent gone away either. Not much they can do about it unless I want to get a specialized surgery for it. Im seriously thinking about it now, as im getting so tired of them. I think i see bugs running around on me. And they float through the sight picture. just been to optometrist, but am making appt with Opthamologist soon. Had my dad to Cleveland Clinic a bunch so i know i like that place and i think i will contact them to. They have an eye department. Thanks Much for your info and good luck with Cataract surgery

 

[Justin Credible]

With magnified optics you are actually looking at a small circle of light (the "exit pupil”) a few inches from the back of the lens. So you want to set your correction to see something fairly close to your eyeball.

Scopes are an afocal system, that is they do not actually create an image behind the scope for you to focus on (if you put a piece of paper behind your scope you will not get an image of what it is looking at, but with a single lens you can as that is a focal system). The light coming out of the eyepiece is collimated, the same as light coming from something that is at infinity (which for all reasonable purposes the things you look at outside tend to be). A "perfect" eye wants to focus at infinity, and it uses muscles to focus at closer things. If you have "perfect" vision, and you set your reticle focus by glancing at the reticle so your eye doesn't accommodate and force itself to focus, the ocular is set to a 0 diopter correction. If you wear glasses for a close correction you will have to crank on a lot of correction on the ocular to avoid eye strain (which is fine if your scope has the adjustment range).

My recommendation is to adjust the ocular to focus without accommodation (forcing your eye to focus) with what you would otherwise wear for vision correction while shooting. If you look at wind charts, data books, target monitor, etc. this might be a reading glass prescription. Just put the glasses on when you set the reticle focus. When someone with good eyes looks through your scope they will think you are crazy, but it will be perfect for you. If you prefer to be able to read the wind flags set the focus while wearing your normal correction. When someone with good eyes looks through your scope it will probably look well focused to them as well. If your eyes are just a little out of whack and you don't wear glasses you can just dial in the focus with no glasses and see things clearly. This is why scopes have an ocular focus (I think it's typically in the +/-2.5 diopter range), to adjust to your eyes/glasses/contacts. If you have something other than a simple +/- diopter correction on your glasses/contacts, such astigmatism, then you will not be able to adjust that out with the scope.

I hope that all made sense!

Justin

 

[KY_Windage]

I have driving/shooting glasses that have a small amount of correction in each lens to give me optimum sharpness (acuity) at long distance. They are what I shoot with, not my reading glasses. I spend an awful lot of time looking through scopes (shooting), and that is what works best for me.

 

[Turbulent Turtle]

Scopes are an afocal system, that is they do not actually create an image behind the scope for you to focus on (if you put a piece of paper behind your scope you will not get an image of what it is looking at, but with a single lens you can as that is a focal system). The light coming out of the eyepiece is collimated, the same as light coming from something that is at infinity (which for all reasonable purposes the things you look at outside tend to be). A "perfect" eye wants to focus at infinity, and it uses muscles to focus at closer things. If you have "perfect" vision, and you set your reticle focus by glancing at the reticle so your eye doesn't accommodate and force itself to focus, the ocular is set to a 0 diopter correction. If you wear glasses for a close correction you will have to crank on a lot of correction on the ocular to avoid eye strain (which is fine if your scope has the adjustment range).

My recommendation is to adjust the ocular to focus without accommodation (forcing your eye to focus) with what you would otherwise wear for vision correction while shooting. If you look at wind charts, data books, target monitor, etc. this might be a reading glass prescription. Just put the glasses on when you set the reticle focus. When someone with good eyes looks through your scope they will think you are crazy, but it will be perfect for you. If you prefer to be able to read the wind flags set the focus while wearing your normal correction. When someone with good eyes looks through your scope it will probably look well focused to them as well. If your eyes are just a little out of whack and you don't wear glasses you can just dial in the focus with no glasses and see things clearly. This is why scopes have an ocular focus (I think it's typically in the +/-2.5 diopter range), to adjust to your eyes/glasses/contacts. If you have something other than a simple +/- diopter correction on your glasses/contacts, such astigmatism, then you will not be able to adjust that out with the scope.

I hope that all made sense!

Justin

That's a good explanation of how it's supposed to work, but for old geezers like me who wear bifocals, there is an extra challenge and lots of people trip over it.

Bifocals are designed and built with your distance correction on top and your near vision correction on the bottom and therein lies the kerfuffle. When I am on the ground behind my F-TR rifle, I am looking through my scope using the top of my glasses, where the distance correction is. It is physically impossible for me to look through my scope with the bottom of my glasses, where the near vision correction is found, the equivalent of the cheaters you buy at the drugstore for $10 to read books.

As Justin said, the eyepiece of the riflescope is an afocal system that requires the lens of your eye to focus on your retina. The diameter of that "ray" is what we call the exit pupil and is a function of objective lens and magnification used. The eye relief if the distance from the last lens where your eye is able to focus the totality of the image emanating from the eyepiece. That is usually a short range around the 3 inch mark.

Since I can never use the bottom of my eyeglasses, I use the diopter adjustment on the eyepiece to focus the reticle to my eye behind the distance correction.

 

[Justin Credible]

That's a good explanation of how it's supposed to work, but for old geezers like me who wear bifocals, there is an extra challenge and lots of people trip over it.

Fortunately, for someone in their mid-40’s, I have not had the experience of bifocals, yet! That does certainly add a level of complication.

Justin

 

[hoz53]

Scopes are an afocal system, that is they do not actually create an image behind the scope for you to focus on (if you put a piece of paper behind your scope you will not get an image of what it is looking at, but with a single lens you can as that is a focal system). The light coming out of the eyepiece is collimated, the same as light coming from something that is at infinity (which for all reasonable purposes the things you look at outside tend to be). A "perfect" eye wants to focus at infinity, and it uses muscles to focus at closer things. If you have "perfect" vision, and you set your reticle focus by glancing at the reticle so your eye doesn't accommodate and force itself to focus, the ocular is set to a 0 diopter correction. If you wear glasses for a close correction you will have to crank on a lot of correction on the ocular to avoid eye strain (which is fine if your scope has the adjustment range).

My recommendation is to adjust the ocular to focus without accommodation (forcing your eye to focus) with what you would otherwise wear for vision correction while shooting. If you look at wind charts, data books, target monitor, etc. this might be a reading glass prescription. Just put the glasses on when you set the reticle focus. When someone with good eyes looks through your scope they will think you are crazy, but it will be perfect for you. If you prefer to be able to read the wind flags set the focus while wearing your normal correction. When someone with good eyes looks through your scope it will probably look well focused to them as well. If your eyes are just a little out of whack and you don't wear glasses you can just dial in the focus with no glasses and see things clearly. This is why scopes have an ocular focus (I think it's typically in the +/-2.5 diopter range), to adjust to your eyes/glasses/contacts. If you have something other than a simple +/- diopter correction on your glasses/contacts, such astigmatism, then you will not be able to adjust that out with the scope.

I hope that all made sense!

Justin

Just read this thanks

 

[hoz53]

That's a good explanation of how it's supposed to work, but for old geezers like me who wear bifocals, there is an extra challenge and lots of people trip over it.

Bifocals are designed and built with your distance correction on top and your near vision correction on the bottom and therein lies the kerfuffle. When I am on the ground behind my F-TR rifle, I am looking through my scope using the top of my glasses, where the distance correction is. It is physically impossible for me to look through my scope with the bottom of my glasses, where the near vision correction is found, the equivalent of the cheaters you buy at the drugstore for $10 to read books.

As Justin said, the eyepiece of the riflescope is an afocal system that requires the lens of your eye to focus on your retina. The diameter of that "ray" is what we call the exit pupil and is a function of objective lens and magnification used. The eye relief if the distance from the last lens where your eye is able to focus the totality of the image emanating from the eyepiece. That is usually a short range around the 3 inch mark.

Since I can never use the bottom of my eyeglasses, I use the diopter adjustment on the eyepiece to focus the reticle to my eye behind the distance correction.

Oh a guy with eyes like mine - thanks

 

[Willie]

I had my shooting glasses made to where I could focus my left eye bifocal on the turret & Anti-cant bubble and still see downrange with the top. My dominate right eye has a different prescription, but I still have to run the ocular adjust all the way out.

I can't find my prescription for the glasses, but they are still working well for me, though I know nothing about how they were made. I have to tilt my head up a bit to to focus the left bifocal on the turret, but it's not often. I call it "my long range reader".

 

[Tommie]

Fortunately, for someone in their mid-40’s, I have not had the experience of bifocals, yet! That does certainly add a level of complication.

Justin

When your age begins with the number 5 crazy (lousy) things start happening.

 

[hoz53]

I had my shooting glasses made to where I could focus my left eye bifocal on the turret & Anti-cant bubble and still see downrange with the top. My dominate right eye has a different prescription, but I still have to run the ocular adjust all the way out.

I can't find my prescription for the glasses, but they are still working well for me, though I know nothing about how they were made. I have to tilt my head up a bit to to focus the left bifocal on the turret, but it's not often. I call it "my long range reader".

long range readers- i like that

 

[hoz53]

When your age begins with the number 5 crazy (lousy) things start happening.

i had coke bottle glasses (very near sighted). since 4th grade -- now at 60+ they havent got better but i feel fortunate ive got it as good as i do.

 

[ScopeAid]

Thanks for this info. I asked the oprometrist today and didnt get much response. Ill be going back soon, so I will find out more.

Check out a prescription attachement we manufacture called ScopeAid sounds like the answer your looking for.

 

[hoz53]

Check out a prescription attachement we manufacture called ScopeAid sounds like the answer your looking for.

ok thanks

 

[BoydAllen]

Scopes are an afocal system, that is they do not actually create an image behind the scope for you to focus on (if you put a piece of paper behind your scope you will not get an image of what it is looking at, but with a single lens you can as that is a focal system). The light coming out of the eyepiece is collimated, the same as light coming from something that is at infinity (which for all reasonable purposes the things you look at outside tend to be). A "perfect" eye wants to focus at infinity, and it uses muscles to focus at closer things. If you have "perfect" vision, and you set your reticle focus by glancing at the reticle so your eye doesn't accommodate and force itself to focus, the ocular is set to a 0 diopter correction. If you wear glasses for a close correction you will have to crank on a lot of correction on the ocular to avoid eye strain (which is fine if your scope has the adjustment range).

My recommendation is to adjust the ocular to focus without accommodation (forcing your eye to focus) with what you would otherwise wear for vision correction while shooting. If you look at wind charts, data books, target monitor, etc. this might be a reading glass prescription. Just put the glasses on when you set the reticle focus. When someone with good eyes looks through your scope they will think you are crazy, but it will be perfect for you. If you prefer to be able to read the wind flags set the focus while wearing your normal correction. When someone with good eyes looks through your scope it will probably look well focused to them as well. If your eyes are just a little out of whack and you don't wear glasses you can just dial in the focus with no glasses and see things clearly. This is why scopes have an ocular focus (I think it's typically in the +/-2.5 diopter range), to adjust to your eyes/glasses/contacts. If you have something other than a simple +/- diopter correction on your glasses/contacts, such astigmatism, then you will not be able to adjust that out with the scope.

I hope that all made sense!

Justin

On just glancing at the reticle when adjusting the eyepiece, a friend finally followed this procedure, after doing it wrong before that, and he had to screw the eyepiece in two full turns to achieve top reticle sharpness. After that, for the first time, he was able to adjust the scope for zero parallax and a sharp target image.