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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Do your eyes change, day to day? (1 Viewer)

longbow

Well-known member
I was out yesterday with my new to me Zeiss 7x42 Classics and was looking at an eagle on the other side of a wide river who was rummaging about on a gravel bar. Focusing, I noted that things were rather blurry. I looked at the diopter setting and saw that they were in their usual place. Cranking on some positive turn, things sharpened up.

This is a phenomenon I have noticed before both with these bins and others. Makes me wonder if my eyes do weird things from time to time.

Anybody else experienced this? Any reason to postulate? Do I need to visit the optometrist?

Thanks.
 
Yes, I sometimes experience such things.

I'll go along for weeks happy as can be, and it seems like all my binos are great. Then my eyes will seem different, and I'll chase diopters around for a couple of days wearing my eyes out in the process so nothing at all looks quite right, and maybe go back to the old setting, or maybe decide my eyes have really changed and stick with a different adjustment.

At 59 years, I can't complain, but I'm starting to get the picture that aging is not a great idea. At this age, it is typical for nearsighted eyes to become more nearly normal, and my eyes are in fact doing this but not at the same rate for both eyes. Pupil dilation is weakening, which affects focus error and astigmatism effects when looking at stars. Focus accomodation is shot to pieces. It's nuts. But my basic visual acuity is still there, I just have to deal with all this stuff occasionally to realize the views I'm after. And its different with every bino. Stuff like this is why for me, a new binocular, however good, is likely to be as much a pain in the rear as bliss.

I'm glad to hear you've got eagles, even if somewhat blurry, to look at with your grand Zeiss ClassiC!
Ron
 
I'm 42 and I get this. Some days my eyesight is better than others. No drastic changes but noticeable differences. I remember getting it when I was a teenager too. I have been very short-sighted since childhood though so it may be to do with that.

Your eye-sight does vary a lot though. Especially if you are ill or run down. That is why, before you have an eye test, the optometrist asks if you've been ill recently. I consider it to be just one of those things. If I were a runner, then I would run faster or slower from day to day so why should seeing be any different.

If I started noticing big differences I would get an eye test though. Straight away. I have one every year whether I feel I need one or not. An optometrist can pick up on other issues from your eyes, like diabetes and high blood pressure, so it's got to be worth it.
 
Day to day?
Hour to hour!
And I'm only(!) 48, though I do spend too much time staring into a computer screen, which can't help.

Having said all this, it you haven't been to the optician for a few years, it can't do any harm to arrange a visit. As Martin says above.
 
Me too. At 48. Apart from "normal" changes flagged by my opto (e.g. more need for reading-glasses apart from my normal workaday specs), I do sometimes feel my eyes have "good" and "bad" days. When we go on holidays to the West of Ireland, and I do a lot of walking and looking out to sea, etc., after a day or two I seem to perceive a marked improvement in my eyesight! (Bizarrely there´s a "holy well" near the village where people used to go on pilgrimage...the water there was said to cure eye-ailments!!!). Constantly changing diopter settings too.
 
Day to day?
Hour to hour!
And I'm only(!) 48, though I do spend too much time staring into a computer screen, which can't help.
.

Scary as we are all about the same age and do the same things.
49 here and stare at a computer for 8-9hrs a day.

I get this too BTW- I assume it's eye fatigue. First time I noticed it I was a little nervous that my bino went south. Then worried my eyes were going south.....

Trip to the Opto and said I'm still 20-20..

Dave
 
I think this has a lot to do with tiredness. When I've worked too much or slept too little (or been sick, as mentioned), I can have a bit of a problem focusing even without binos, and I'm (only) 35.

Put eight or even ten times magnification to that and there is no wonder why one keep adjusting the diopter and focus back and forth. After a good nights sleep or so everything is as it should again.
 
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There is a long list of reasons why our eyes change. As we all understand, the aging process is relentless. Maxine would say, "Youth is a wonderful thing. Too bad it is wasted on the young." My first wife, who died from diabetes and eventually went blind, had problems with fluctuating blood sugars affecting visual acuity.

But it would be a mistake to infer from my above comments, that your problem is disease related. Only a competent trained medical professional can make a proper diagnosis. Periodic eye exams certainly make sense.

I believe anyone with a rudimentary grasp of the aging process understands that our eyes are not exempt. I also believe that the inevitable changes usually come gradually, so our awareness is also gradual.

As our optics become super refined, it is possible that some of us (myself included) can't see the "gains." And perhaps it is just old eyes and old brain cells that are at work.

John
 
Nice to know I am not alone! I am 45 and had not had any issues like this at all, until I developed vertigo in 2008. It created substantial visual issues for me (even with glasses) that seemed to have resolved for the most part, but I have noticed that I really have good visual days & some really bad. I spend a lot of time adjusting the diopter like others above - very frustrating. I know that after 40 we all, or most of us, experience some loss in visual acuity, but I felt this was a little more than that. I agree with John, age (& disease) can be relentless - just wish it didn't make me frustrated with a beloved hobby at times.
 
One thing I noticed is that when my eyes don't seem to be working properly, my blood pressure is usually raised so you all might want to have that checked out ;)
 
When it is cold and/or windy, I find that just the difference between how much my eyes water affects the balance between them and thus the optimal diopter setting. The effect is so transitory, sometimes differing minute to minute, that I resist changing the setting.

But here's another thought. I have found that the moving ocular focusing system of the Zeiss 7x42 Classic, or at least some units of the model, is affected by temperature. It's not so much an obvious change in focusing stiffness (though there is a bit of that under both very hot and cold conditions), as a change in the symmetry of the yokes/bridges that connect the oculars to the central drive. You can check if this is happening with your unit by turning the focus such that the oculars are as close as they can be to the body of the bin, and noting the width of the little gap between the ocular and the rubber armor of the body. Next use them for a while at a very different temperature, and then check that gap again. In my unit, there is a bit of a thermocouple effect. The gap is symmetrical at "room temp" but when hot one ocular sticks out a bit more than the other, and when cold the asymmetry is reversed. The gap difference can be compensated for using the diopter adjustment, but the whole effect is irritating enough that it contributes to my favoring other bins most of the time. I sent them to Zeiss USA for repair (and explained the problem in detail) several times, and the last time around they seem to have improved operational stability (the only thing obviously done each time was lubricating the focus mechanism), but I had given up by then.

--AP
 
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Me too! Until I saw this thread I often wondered why my binoculars/eyes varied from day to day. Using the same test targets every time, eg. 'Cisco Systems' lettering only 1cm high, or about half an inch, on a roof aerial three houses away, or the mounting brackets and bolt-heads on a street lamp (and even the cobwebs on it at night, lit up by the light), sometimes these would be easily picked out, yet other days I'd need to fiddle with the focus and dioptre adjustment. When I tried this a couple of days ago, I swear my sharpest binocular seemed to be one of my oldest, a Nikon 7x35A, despite being pitched against Nikon 8x32SE, Nikon 8x42HG and Zeiss 10x40BGAT. There are days when I find it difficult to read the lettering, even though I know what it says, yet on other occasions it 'jumps out' clear and sharp. One thing I have noticed, however, is that when I use a tripod to mount a binocular on, everything becomes clear to me, literally, so perhaps therein lies the solution if you're having 'a bad bin day'; your eyes may not be the culprits, but your hands. Using a lower magnification could contribute to a better view (reduced shake effect). Indeed, a 1943 IF 6x30 U.S. Navy 'BuShips' Mk.XXXIII (Universal Camera Corp. N.Y.) provides a nice sharp image notwithstanding its 67 years, because it's only 6x and each eyepiece can be independently fine-tuned to perfect focus (and with greater facility if tripod-mounted) though admittedly hardly ideal for birdwatching...
 
I'm 49 as well. When I turned 40 suddenly my vision began to deteriorate progressively from perfect 20/20 to needing (up to) 3.5 reading glasses (depends on distance). I also find that sometimes reading glasses aren't enough and I need more light.

I take supplements like folic acid, fish oil, vitamin D, etc. - just in case I am vitamin deficient because I don't really have a healthy diet.

I'm going to take a vision test here now: http://www.myvisiontest.com/register.php
 
Holy Smokes, thanks a lot for all the great responses. I was a bit timid in posting the original question, as I figured I might just be a bit neurotic or OC or something. Nice validation, especially from you young folks (in your 40's). Although I am now 60 and not in great health, I have as I said, noticed this in years past. For some reason I never thought of the eyes as muscles that would fluctuate in ability to their job.

I'm also going to take the good advice and make an apt. with the eye Doc.

Am constantly amazed at the level of knowledge on this site since I joined and this thread has proved the point once again. :t:
 
Nice thread. This is something that affects me too. I do think that whether or not I feel good, say if I have a headache or am tired really magnifies the effect too. But at 62, I'n not possessed of the eyesight I once had. However overall I have no complaints with my eyesight. It is nice to see it effects other people besides me.
 
After a good nights sleep or so everything is as it should again.

I think that is what I need to cure my tired 40 year old eyes!!!!
 
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