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Discussion Starter · #1 ·
I'll turn 57 next month. Last year I gradually lost the ability to focus on the front sight. With my handgun shooting I can see a blurred front sight, a burred rear sight, and of course a blurred target. I can't really SEE my M1A's front sight. I worked with a man when I was a deputy in Texas who was in his 50's and he had the same problem. He worked something out with his optometrist and solved his issues. Is there a nationally known optometrist that I can send my prescription to along with what I need for shooting? Or do I just need to work with my local optometrist?
 

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I'll turn 57 next month. Last year I gradually lost the ability to focus on the front sight. With my handgun shooting I can see a blurred front sight, a burred rear sight, and of course a blurred target. I can't really SEE my M1A's front sight. I worked with a man when I was a deputy in Texas who was in his 50's and he had the same problem. He worked something out with his optometrist and solved his issues. Is there a nationally known optometrist that I can send my prescription to along with what I need for shooting? Or do I just need to work with my local optometrist?
This is all you need no need to pay a doctor.
http://shop.shootingsight.com/Safety-Shooting-Glasses-Shooting-Glasses.htm
 

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I'm only 39 and I struggle with focusing on my front sight. I put a scope on my JRA M14F and even though it adds weight to an already hefty rifle, I figure if my scope helps me hit my target, for me it is worth the extra weight.
 

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Discussion Starter · #5 ·

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Discussion Starter · #7 ·
How do you wear them?

Am I keeping my glasses on then donning the corrective safety glasses in front of my own glasses?
 

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I am 73 and find that the .5 lens in the hooded rear sight is a real plus for me to be able to clearly see front sight and bulls eye. Feel confident that w/ hooded rear sight aperture and the lens insert will help with your problem and conversation w/ Shootingsight could get you started in the right direction.
 

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Discussion Starter · #11 ·
Handgun too

I'm as concerned about seeing my Glock front sight as I am my M1A front sight. I shoot my Glock a lot more than my M1A for right now. I'm going to end up scoping my M1A, but, I'm saving for a Nightforce ATACR F1 5-25x50. Nightforce are one of the only brands that can handle all the vibration an M1A/M14 produces, and out of the brands that can handle it, the Nightforce is the top brand.
 

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I'm the "old guy" in the thread mentioned above. Along with thinking about trying the single vision lenses to add diopter correction/adjustment, it's probably a good idea to get a current exam as a baseline to determine what your vision situation actually is and any differences between the two eyes. That will help determine the types of corrections needed. Turned out a simple single correction as in the inexpensive shooting glasses mentioned above won't work particularly well for me.
 

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Using lens math from photography, you can calculate the offset in lens power between perfect distance vision, and perfect shooting vision.

Your eye has one theoretically perfect focal point, if you take an object and move it away (or closer) than the perfect focal point, it will develop a line of blur around the edges. However, because the limit in resolution of the human eye is about 1MOA, if you shift an object’s distance such that the blur around the edges remains less than 1 MOA wide - your eye cannot see the blur, and to your brain the object stays in perfect focus.

So while your eye has only one theoretical focal point, there is actually a range, from somewhere closer to your focal point, to somewhere beyond your focal point, where the object appears to be in perfect focus. This is called your depth of field.

As a shooter, what you ideally want is to set your focal point such that your depth of field is centered between the front sight and the target, so the front sight falls just inside the near edge of your depth of field, while the target falls just inside the far edge of your depth of field, and you can see both clearly at the same time to aim. This magical distance that exactly centers the focal point is known in photography as the hyperfocal distance, and we know how to calculate it very precisely.

The problem older shooters face is that the focal power of the lens in your eye is variable, driven by the Ciliary muscle in your eye. When the muscle relaxes, your lens is low power and focus goes to distance, when you exert the muscle, it deforms the lens so it adds power to the lens, and your focus comes in close. Unfortunately, past about 40 years old, the lens in the eye gets hard, and you lose this adjustability range – so much so that bringing in your focal point to be able to see and hold the front sight is beyond what the eye muscle can deliver. Or at best, the eye can do it for 1-2 seconds before the muscle is overly fatigued, and it starts to give up, so you can see the front sight fade if you take more than a few seconds to break the shot. So this is the problem we are trying to solve in shooting – how to allow the eye to focus at the hyperfocal distance without straining the eye muscle.

Luckily, there is an easy solution. Lenses are additive; if you stack one lens on top of another, their powers add. So another way you can add power to your eye’s lens, without exerting the muscle, is to place a positive power lens in front of your eye. This will shift your relaxed focal point from being in the distance, to being closer in. The stronger the power of the lens, the closer it shifts your focal point. So if we know the hyperfocal distance for a rifle, we can calculate the necessary lens power to shift our focal point from infinity to this hyperfocal distance.

Without actually going through the math, the answer is that for a long rifle, M1 or M14, you need to add a +0.5 diopter lens to focus. For an AR or pistol, which have shorter sight radius, you need to add +0.75.

Unfortunately, the easiest lenses to come by are reading glasses, and these are all too strong. The lowest power is usually +1.25. This lens is powerful enough to bring your focal point back to arm’s length, for reading. But for shooting, the focal point is so close that the target is completely fuzzy.

This is why I have worked with a safety glasses company to make shooting glasses with the correct powers molded in. If you have good distance vision, and just need cheaters for reading, these are the glasses for you. If you do need distance correction, but wear contacts, these glasses will also work for you.

If you have distance vision correction and wear glasses, the answer is to talk to your doc (or order glasses on-line at places like Zenni Optical), and get a pair of glasses that have your distance vision prescription in them with either +0.5 or +0.75 added to the lens strength.

With these glasses you will be able see the front sight as well as you did when you were 18.
 

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Discussion Starter · #14 ·
Distance vision

I do wear progressive bifocals. My distance vision isn't awful. Due to my pupils dilating to 8mm my Lasik ophthalmologist first had prosthetic lenses implanted that had some correction built in as well as an anti-glare coating. For about two years I had 20-15 vision. That was GREAT! But, I was 49 when I had that done and of course, my vision has slipped a little. It's 20-40 in my left eye and 20-35 in my right eye. I always had to wear reader glasses - I never could focus well enough to read. I had a pretty bad astigmatism in my right eye. I don't know if the Lasik took care of that or not.

Bottom line is I need to wear glasses for distance correction, and the bifocal for reading. I can't wear contacts now due to the Lasik surgery. It flattens out the cornea and makes fitting contacts very, very difficult.

So, I need prescription glasses with a spot I can look through and once again be able to focus on the the front sight at handgun distance. I can put a scope on my M1A. I had planned on doing that anyway.
 

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Your answer is to take your distance prescription and add the +0.50 or +0.75. While this will blur distance just slightly, the focus you gain on the sight is much greater than the focus you lose on the target.

If you want to email me your prescription, or post it here, I'd be happy to go through the math with you.
 

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A symptom of micro-cateracts is that when you look through a small aperture, it looks like there is a small ball of dust, or a spider web in the middle of the aperture opening.

I'm not a doctor, so I don't know if these micro cateracts are any indication of 'normal' cateracts. There are a lot of shooters who can see fine, except through small apertures.
 

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So if my distance vision is fine but use 1.75 readers what would I need for Garands and M14. If I shoot with the readers on the front sight is clear but target is fuzzy. Of course without the readers its the other way around. Thanks
 

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Am I keeping my glasses on then donning the corrective safety glasses in front of my own glasses?
I just use the corrective safety glasses +.50, no need for my prescription glasses. I am far sighted have bad near sight vision.

The shooting sight glasses work great.

Good Luck
 
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So if my distance vision is fine but use 1.75 readers what would I need for Garands and M14. If I shoot with the readers on the front sight is clear but target is fuzzy. Of course without the readers its the other way around. Thanks
If your distance vision is fine, you want +0.50 to shoot a Garand.
 
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