Vision Correction for Shooters

I thought I should start a new topic title because we're no longer discussing cataracts/surgery.

Thanks for the postings from jmdavis and mikemyers as the contents are helpful for our shooters.

jmdavis wrote:One reason the knoblochs may work better is that they may be parallel rather than at an angle to the eye

Both Knoblochs and Champion shooting glasses offer many adjustments, but they offer little protection and we may need to be concerned with the longer vertex distances (distance from the eye to the lens).  With thick spectacle lenses and larger sizes of the more conventional shooting glasses, looking slightly sideways may cause the prescription to change and also would induce prism, possibly causing BE Mike's errant shot groupings.  Still interested in his sand bag testing results.

Right now I need +1 for normal distance with my shooting eye. I have tried, +1.5, +1.75, +2, and +2.25 for irons with the 22 and Service Pistol. With good light (i.e. Perry) and no cover, I like the +2.0. In dimmer light, I like the +2.25. With the airgun indoors in good range light, I wind up using the +1.75 or the +2.0.

Well stated, and to clarify, the +1.00 distance Rx need to be subtracted from the total resultant Rx to understand the various lens power adds.  We would then read, "I have tried +0.50, +0.75, +1.00, +1.25 (adds)...."  The reason for the different powers, besides the sight radius, would be the pupil sizes as related to the lighting.

I have the paddle and also a +.125 lens for tweaking. It should be noted that getting a +.125 scrip generally means that there will be no anti-reflective coating on the lens. Maybe Xmastershooter can address that, but that is my understanding.

I'm not sure what is happening here but anti-reflection (AR) coating can be added onto any lens.  All my top level and serious shooters get the AR coating.  Keep in mind that there are different quality levels and is reflected upon the price.  I use only the top-of-the-line coating.  The cheaper ones smudge easier, flake off easier with handling, and do not work as well.

In concluding, I would recommend that people not just start buying lenses. Even though you can get them for $16-$40 each, some research will help you to not wind up with a collection of 15 or 20 lenses.  Talk to your optometrist. Read XMastershooter's writings on the subject from Ed Hall's page. Check out a variety of online resources, then make decisions.

As I mentioned before, I'll be adding onto my original "Bullseye Shooters' Guide for the Eyecare Professional" and have contacted the managing editor of Shooting Sports USA.  I've been told that this has been a very popular article for the readers.  I'll also provide this to Ed Hall as his site will show everything in its entirety, as the Online magazine may edit out some important details.  Thanks Ed!

mikemyers wrote:
Not sure if anyone else would like this, but I did all the above only for my shooting eye.  For my other eye I set them to the distance to my bench top, for working on the guns, reading, adjusting the sights, etc.  All of them should be polycarbonate.  IMHO.

I spend almost as much time determining the non-shooting eye Rx as I do with the shooting eye Rx.  There are many possibilities.

Thanks xmastershooter. That is very valuable information and you made what I wrote more understandable. Then again, I am a computer guy, so...

Norman,

You're forgetting that awesome-looking "construction contractor's eyeglasses" easily add 10 points to your score.

Mmmmmmm.........."Look bad-ass, shoot bad-ass!"  Not bad.

Just when I thought had my pre-match meditation mindset:  "Train hard, shoot easy!"

xmastershooter wrote:

......Well stated, and to clarify, the +1.00 distance Rx need to be subtracted from the total resultant Rx to understand the various lens power adds.  We would then read, "I have tried +0.50, +0.75, +1.00, +1.25 (adds)...."  The reason for the different powers, besides the sight radius, would be the pupil sizes as related to the lighting.......

Think of this as a camera.  

If you focus the camera perfectly on something, it will remain in focus regardless of what you do to the aperture (pupil).

Depth of field increases as you make the aperture smaller (pupil, reacting to bright light).
Depth of field decreases as you make the aperture larger (pupil, reacting to low light).

If your purpose is to see the front sight clearly, at any aperture, the focus must be set precisely on the front sight.

If the focus isn't precise, as the lighting changes, and the pupil changes size, things not at the precise focus distance will seem to be getting sharper or less sharp.

None of this changes the "focus".  Focus of a lens means things only at one specific distance will be in focus.  Because of depth of field, things at other distances may appear acceptably sharp.



None of the above applies if you have multi-focal IOL's, or adaptive IOL's, or other unusual combinations that may change the focus of your eye.  If for some reason, your eye changes focus, that will definitely change the sharpness of your front sight.  Not sure about others, but now that I have an IOL in my eye, if my front sight is perfectly in focus, that never changes for me when the lighting changes.  Other things, at other distances, do appear more or less sharp to me based on the lighting.

xmastershooter wrote:Mmmmmmm.........."Look bad-ass, shoot bad-ass!"  Not bad.

Just when I thought had my pre-match meditation mindset:  "Train hard, shoot easy!"

"Train hard; shoot easy; look fantastic!"

Deny the power of the X-ray specs at your own peril.

john bickar wrote:

xmastershooter wrote:Mmmmmmm.........."Look bad-ass, shoot bad-ass!"  Not bad.

Just when I thought had my pre-match meditation mindset:  "Train hard, shoot easy!"

"Train hard; shoot easy; look fantastic!"

Deny the power of the X-ray specs at your own peril.

Can you guys see through those things? 

I had some rifle students insist on buying look cool glasses with inserts. The results weren't what they had hoped for. The inserts never seemed to line up for shooting from position. 

The issue of safety with champions and knoblochs (or Vargas) is legitimate. Most of my shooting of pistols is wearing glasses with side shields. But I shoot the ball gun and the 22 with irons using Champions or Vargas because I have the lenses for them to make them work. I do use an offside blinder and side shield and haven't had issues with blowback with rifle or pistol.  I have thought of Randolf's or hy-wides but my scrip particularly for irons changes from winter to summer. 

One friend who is 80 had a set of Hy-Wides made up by Alan Toler to place the center of focus for the front sight in the position for rifle prone. Before scopes, my vargas had different lenses preadjusted for different positions (sitting, prone). I also had a pair of Junker glasses from Neal Stepp for offhand (which also worked for sitting). 

My testing has included lens tints. But I wound up with the basic tint that many people are using around here, light to medium purple. 

Again, I appreciate this subject. It's hard to know what is you, what is the gun, and what is your eyes sometimes. But it seems like finding the right thing is a process and compromise rather than a simple decision.

jmdavis wrote:

john bickar wrote:

xmastershooter wrote:Mmmmmmm.........."Look bad-ass, shoot bad-ass!"  Not bad.

Just when I thought had my pre-match meditation mindset:  "Train hard, shoot easy!"

"Train hard; shoot easy; look fantastic!"

Deny the power of the X-ray specs at your own peril.

Can you guys see through those things? 

I had some rifle students insist on buying look cool glasses with inserts. The results weren't what they had hoped for. The inserts never seemed to line up for shooting from position. 

The issue of safety with champions and knoblochs (or Vargas) is legitimate. Most of my shooting of pistols is wearing glasses with side shields. But I shoot the ball gun and the 22 with irons using Champions or Vargas because I have the lenses for them to make them work. I do use an offside blinder and side shield and haven't had issues with blowback with rifle or pistol.  I have thought of Randolf's or hy-wides but my scrip particularly for irons changes from winter to summer. 

One friend who is 80 had a set of Hy-Wides made up by Alan Toler to place the center of focus for the front sight in the position for rifle prone. Before scopes, my vargas had different lenses preadjusted for different positions (sitting, prone). I also had a pair of Junker glasses from Neal Stepp for offhand (which also worked for sitting). 

My testing has included lens tints. But I wound up with the basic tint that many people are using around here, light to medium purple. 

Again, I appreciate this subject. It's hard to know what is you, what is the gun, and what is your eyes sometimes. But it seems like finding the right thing is a process and compromise rather than a simple decision.

that's why i got me one of those clear sight loops that swing down.

xmastershooter wrote:Both Knoblochs and Champion shooting glasses offer many adjustments, but they offer little protection and we may need to be concerned with the longer vertex distances (distance from the eye to the lens).  With thick spectacle lenses and larger sizes of the more conventional shooting glasses, looking slightly sideways may cause the prescription to change and also would induce prism, possibly causing BE Mike's errant shot groupings.  Still interested in his sand bag testing results.

BTW, I was looking at the rear sight of my 1911 while shooting at the indoor range yesterday and it is cranked way to the right also. This still points to my thick shooting glasses as being the problem IMHO. It'll be a while before I can get out and do some sand bag testing. I'll probably get to test some different glasses before then, however.

When you had your glasses made, did they mark the exact spot on each "original" lens that was in front of the pupil of that eye?  For my target glasses, they did this for me last week.

Having read what you posted, I tried something new.  My progressive lenses have a "plain" top part, no prescription, with an increasingly strong prescription in the lower part.

When I moved my glasses back and forth (right and left), the top part, plain "glass" had no effect whatever.  The image was stable.

BUT, when I tried this with anything in the lower part of the glasses, moving the lenses either way caused what I was looking at to move the opposite way.  

Next step was to try it with one of my new shooting glasses.  Same thing happened, moving the glasses slightly away from my nose, so I could move them right and left caused "the world" to move the other way.

I can't try this now (no gun), but maybe one of you can.  If "the world" moves to the right, because of your glasses being moved, the front sight should also move the same way, so maybe that's not an issue.  But if the rear sight moves more or less than it should, that would throw off your aim - maybe what you've been describing above?

I'm too sleepy to think this through.  If the sight picture and sight alignment remained the same, it shouldn't make any difference.  Otherwise???

Also, for reasons I don't yet understand, they need to mark which exact spot on each lens is directly in front of the pupil. Anyone know the reason?

I shoot mostly with single vision glasses. Distance for dot and front sight distance for irons. If using regular glasses I have experimented with bifocals and also with mono vision reading lenses in the off eye. Bifocals are ok, but can be distracting in the shooting eye (my experience only). 

I can answer your question about moving the glasses. It does change things. That's why I like the Champion frames with custom lenses. I can set up the lens as I want it and tweak it for best performance. 

For example, if I switch from a distance scrip using shooting frames to using regular glasses with a distance scrip. There is a shift in zero. But I also have awindage zero shift from indoors to outdoors. A perfect zero on a well lit indoor range will go left with the same glasses outdoors in even lighting (at least on the outdoor covered ranges I shoot on).

john bickar wrote:"Train hard; shoot easy; look fantastic!"
Deny the power of the X-ray specs at your own peril.

Errrr, I'll be sure to keep my wife and daughter a safe distance!

mikemyers wrote:When you had your glasses made, did they mark the exact spot on each "original" lens that was in front of the pupil of that eye?  For my target glasses, they did this for me last week.

Also, for reasons I don't yet understand, they need to mark which exact spot on each lens is directly in front of the pupil. Anyone know the reason?

I have worked for years on the perfect glasses for riding motorcycles at the track, with enough success that the optometrist shares my method with other interested riders.   

The marking of the pupil is because all lens grinds are a compromise.    When a lens is made, it is ground larger than the final cut to the frame.   It has a "sweet spot" where the correction is the truest to the prescription.    You want that spot located in just the right spot where your eyes are during the task the glasses are for.    Since my riding glasses are for full face helmet in a "tuck",  we always mark the centers with my head down and me looking through the top of the lens.   It works.   After the lab knows the desired optical center, they cut the lens blank in the position to put the lens center where you want it.   When they screw up it can vary from feeling the prescription is not right to instant headache.  Also, similar to substituting generic drugs for name brand ones, optical labs often substitute different lens grinds for what your optician prescribed.   Very important for our types of lenses to have Dr. write "dispense as prescribed" to avoid getting something close, but not quite what you had hoped for.

For shooting glasses, you should have them mark the centers when you are holding your head in the same position to the sights as when you are shooting, for me that is about 15 degrees off from perpendicular.

mikemyers wrote:Also, for reasons I don't yet understand, they need to mark which exact spot on each lens is directly in front of the pupil. Anyone know the reason?

Your optical lab sets up the lenses in relationship to the frame manually.  Often times, one's nose may be offset so the frame would fit laterally off to the right or left of the face.  Also, if we draw a vertical mid-line down one's face, the right and left sides are different.  A binocular P.D. gives the total measurement between the right and left eyes, for example, 66mm.  When monocular P.D.'s are taken, we may get 32mm. in one eye and 34mm. for the other eye.  Our pupillometer can measure both.  The technicians can then input these measurements to a computerized lens edging machine without the dotting.  Manual dotting takes practice to be accurate.

This may help everyone who wears eyeglasses, especially bifocals and progressives.  How many times have you picked out an eyeglass frame and the tech takes measurements for the height?  When you pick up the eyeglasses, they would adjust the frame.  Well duh!  Now you may have lenses that don't fit because the frame adjustment is different and the lens placement will now be different.  Frames should always be adjusted to the proper fit prior to any measurements taken or dot markings.  Another pet peeve is when the technician measures the height, they may lift or lower your head to the position that they think is correct.  Duh again!  They just moved your head to a position that is not your normal position.  Lastly, does the technician asked what is your occupation and hobbies?  If no, duh again!  This will determine how the lenses should be placed into the frame.  Too many duhs in the optical field nowadays, and the doctors may know even less than the techs.

Aprilian
"The marking of the pupil is because all lens grinds are a compromise.    When a lens is made, it is ground larger than the final cut to the frame.   It has a "sweet spot" where the correction is the truest to the prescription.    You want that spot located in just the right spot where your eyes are during the task the glasses are for...."




That leads to all the rest - once again, after reading your comment, it now sounds "obvious", but it wasn't obvious to me before reading this.

I see a lot of people shooting with their head angled forward, (as if they're facing the ground), looking "up" with their eyes at the sights.  This means they are not looking at the same place on the glasses that the technicians expected (as you wrote).  

Maybe this contributes to some of the problems people are describing, as how their glasses affect their shooting?

(My head always wants to "fall" forward, but then I notice it and look up, straight ahead.  I think I do this because my hands gradually lower due to the weight of the gun.  I constantly have to remind myself to raise my hands so the sights are in front of my eyes, not my eyes being lined up with the sights.  Don't tell Jon - he'll instantly notice that this is yet one more way I am not being consistent from shot to shot....)    

mikemyers wrote:When you had your glasses made, did they mark the exact spot on each "original" lens that was in front of the pupil of that eye?  For my target glasses, they did this for me last week.

When I had the lenses made for the Randolph Engineering glasses, I sent off the prescription with pupillary distance. That might be the problem with these thick lens "iron sight glasses". I have another pair of Randolph shooting glasses with the thinner lenses. They have a mild correction in the top for shooting a dot and bifocal for reading score cards, scoring, etc. I haven't had any problem with them.

BE Mike wrote:When I had the lenses made for the Randolph Engineering glasses, I sent off the prescription with pupillary distance. That might be the problem with these thick lens "iron sight glasses". I have another pair of Randolph shooting glasses with the thinner lenses. They have a mild correction in the top for shooting a dot and bifocal for reading score cards, scoring, etc. I haven't had any problem with them.

The P.D. was not your problem.  That is a finite number and doesn't affect thickness.  The size and shape of the frame, and the material along with the prescription determines the lens thickness.  You mentioned that one pair had an iron sight Rx and the other bifocal, two different prescriptions.

I wondered what was being discussed in this forum when it first started, and found a link to this page.  I think it has a lot of useful information for what's now being discussed:

http://www.starreloaders.com/edhall/nwongarts.html

....and more specifically:

http://www.starreloaders.com/edhall/nwongmain/inaceyeg.html

mikemyers wrote:I wondered what was being discussed in this forum when it first started, and found a link to this page.  I think it has a lot of useful information for what's now being discussed:

http://www.starreloaders.com/edhall/nwongarts.html

....and more specifically:

http://www.starreloaders.com/edhall/nwongmain/inaceyeg.html

Mike, xmastershooter is the author of the information in the links above

Thanks!!  I didn't realize that!

I went to Tirunelveli, India, to take photos of a conference mostly related to Glaucoma, but the last few speakers concentrated on IOL's.

I don't know enough to even begin to explain the things they talked about, but getting an IOL for the absolutely best vision is not a simple matter of getting the biometry done, and ordering the appropriate IOL. There are tests and measurements, that take into account many factors that affect the sharpness of the image.  Similarly, for multi-focal IOL's, there are tests that can be done ahead of time that will show whether a multi-focal IOL is appropriate for a specific person's eyes.  

Aravind did do a test for me a year ago, that showed what the image on my retina looked like at that time (with cataract), and what it would look like with a mono-focal IOL.  They use a capital-E for the test.  This may or may not have been the same thing people were talking about today.

I think the conference was video-taped.  Not sure.  If so, I'll ask if I can get a copy of those segments, that I can post a link to here. The discussion was for ophthalmologists, meaning that for much of it, I didn't understand the details, only the overall purpose and function.  It was a conference for doctors, not ordinary people - which was great, as it discussed things I never knew anything about before.

The important thing, is that all of this testing be done before the surgery, and that the patient and doctor should understand each other.  The doctor needs to know if the patient doesn't want to wear glasses, OR if the patient needs perfect vision.

I'm having trouble with my red dots not being dots but more like an 8 or even a clover configuration.  I'm scheduled for an eye exam next month and am wondering if a new prescription will fix this or do I need a prescription specifically for shooting as opposed to everyday use.  BTW I'm 55 and wear bifocals mostly for reading and a slight distance correction.

Thanks for any advice.

Pat

If you turn down the brightness of the red dot, does that help?


I read here where some people say to focus your eyes on the dot, and others say to focus on the target.  After reading a lot here, I decided I would do the second, so my new "red dot" prescription is actually my prescription for seeing at a distance with my glasses.

I think I've read here where the clarity of the "dot" depends on which red dot sight you use.  I've only tried two, but for me the "Matchdot II" seemed to have the sharpest "dot", especially when the brightness was turned down.


(You didn't say, but whatever you wear, it ought to be polycarbonate material for safety, either a single lens, or bifocals, or those special "utility" lenses where most of the lens is one prescription, but there are two "D-shaped" insert areas with a different prescription.  Whatever you get, my advice is safety comes at the top of the list.  That includes a sturdy frame, and large lenses to cover more of the area near the eye.)