I got an email from an old friend (emphasis on the old, for both of us) in which we were talking about shooting under the infirmities our advanced ages have provided us with. At one point the conversation turned to vision and peep sights and Tom said this:
Up until recently, I had to shoot with one eye closed, either the left, when shooting right handed or the right when shooting right handed. Something has changed, because now… I cannot shoot left-handed any other way than with both eyes open. IF I close my right eye, I cannot see anything, period. Can’t find the target, can’t find the peep. I also cannot shoot at all with my glasses on. I must shoot without my glasses … which at first gives me a terrible double image until I get to anchor and look through the peep and scope. Then there are two target images, but I’ve learned to ignore the “dummy” target and focus on the correct one. The tough part is looking down range and seeing double of everything and the double is “moving” from low left to upper right.
I cannot see for beans up close to set my sight, however.
It is nice to be able to shoot with both eyes open. … after nearly 50 years of having to shoot with one eye closed!
Of course, the internet is the modern equivalent of the general store cracker or pickle barrel, so I had to chip in with my two cents on the topic:
As we age a number of things change with our eyes. One I noticed is that our irises slow down. I discover this the hard way; I was out driving at night, and my eye’s irises opened up to let in more light and then I turned a corner and a asshole driver coming the other way had his high beams on and I was blinded. I couldn’t see for a couple of seconds and was driving from memory of the road (I realized this later when I did a mental replay—thank you, archery!). Having a flood of light pouring into my eyes, my irises immediately but slowly started cinching in smaller and smaller … just in time for the return back to low illumination driving and my irises, now too small, slowly opened up again, extending the time period in which I was driving blind. This is a common source of why older people no longer like driving at night—scares the bejebus out of us.
When you swing a peep over your aiming eye, you are blocking part of the light (the reason for the danged peep in the first place), but because our irises change slowly (1-3 seconds?) compared to those in young eyes, this doesn’t happen comfortably in the time you want your shot to go off. By keeping your off eye open, the fraction of total light being blocked by the peep coming through both eyes is smaller, resulting in a smaller iris correction and better vision.
Using a peep with a smaller hole actually improves your vision by reducing the number of aiming eye lens defects the light travels through. but outdoors, in low light … well, there is a reason hunters use peeps with larger holes than do target archers. The smaller hole allows in less light and….
By the way, you can get “shooting glasses” made in which the optical centers are off to the left (for right-handed archers). We think we turn our heads 90° to look over our shoulders, but in reality, we turn our heads just far enough to see past the bridge of our noses. (Turning our heads farther results in an aching neck and headaches!). Ordinary glasses are built assuming you are looking straight outward and do not work anywhere near as well as your eyes move off of that axis.
Note Normal head rotation, according to one study is “Head-neck rotation was symmetric, and associated with concomitant movements in both the sagittal and frontal planes. It was larger in women (162°) than in men (155°), and performed with limited adjunctive thoracic motions.” This is about 77° (for men) in each direction and I think that gets less with age. (It sure feels like it to me.) Being able to turn our heads on our necks less means there is a smaller window to look through, one closer to the bridge of our noses and therefore more “off axis” for our glasses. I think I have benefited quite a bit from getting shooting glasses, which fit closer to the bridge of my nose and have optical centers in that direction.