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Possible source of veiling glare? (1 Viewer)

John Frink

Well-known member
OK, here’s a question for all the older bino-freaks out there. A few days ago I was running at sunrise in the park near our house. I don’t wear my glasses when I’m running. I was headed east, and as I crested a small rise and faced the rising sun I suddenly experienced overwhelming veiling glare in both eyes! I had to look down and shade my eyes to see where I was placing my feet so I wouldn’t run off the path. I am old, and I know my internal optical components are no longer perfectly clear, so I wasn’t surprised to get some glare from the sun; but this was massive, far more than I expected.

So here’s my question: when someone on this forum criticizes a particular binocular for being especially susceptible to veiling glare when viewing at low angles toward the sun, should we respond by asking the individual to consider whether he or she might actually be seeing glare produced by his or her own less-than-perfect eyes, and that the binocular in question might not actually be the source of the glare? Should there be an age-test for veiling-glare reporters?

I just thought I’d try to start a discussion on this topic.

Cheers,

John
 
Possible snow blindness caused by sudden overwhelming stimulation of eye/brain system.

I went blind for about ten minutes suddenly when reading against a white tablecloth.

P.S.
Other thoughts.
You may have been partly dark adapted and the sudden sunshine did not allow natural readjustment to increased light.
You were running, so body exertion may be partly the cause.
Has it happened before?
All speculation on my part.

A good opthalmic test could reassure.

I mainly test for veiling glare/flare and ghosts at night, and the streetlights used are not bright enough to cause me problems.
It is fairly easy to see which binoculars are good or bad.
 
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At age 67, I can just see the beginning cloudiness of a cataract in one eye when reading a well lit printed page. My sensitivity to internal eye light scattering in situations like described above seems no worse however than when younger. Eye scattering is noticeable in the same kind of situations that would induce it in a binocular: looking into shadows with bright sky overhead, or trying to look near the sun.

But when viewing in these situations with a binocular, although the intense unwanted veil-inducing light enters the objective lens and can pollute the binocular's image, the binocular itself shields the eyes from the bright regions of the object field. So, I don't think it's likely to mistake veiling glare in the binocular for what is actually happening in the eyes.

Ron
 
Especially for something as condition-specific as glare, I would think that a direct comparison with a pair of known "benchmark" bins would be required for an observation to have much meaning, regardless of the age of the observer. That said, our eyes change as we age, although in different ways for different people. I can imagine that my mid-fifties eyes no longer have the acuity to distinguish contrast and resolution as well as someone in their 20s or 30s, even to the extent that two sets of bins might appear to be equivalent to me whereas they might see a clear advantage in one over the other. On the other hand, my pupils still dilate as much as when I was younger so my ability to discern differences in image brightness in low light conditions might not have diminished as much. No disrespect intended of course. Age or die, right?
 
A family member has cateracts and is due to be assessed for surgery shortly. Apparently she has a diffuse cortical rather than the nuclear variety and her acuity is only modestly affected. However glare has become a big problem. Even quite peripheral car headlight are blinding. Daylight is quite complicated as matters seem to improve with a contracted pupil, but bright reflections are a particular hazard as they are unpredictable, and even a bright cloud base can severely reduce contrast. She's not a binocular user, so can't comment on how things might compare.

David
 
A family member has cateracts and is due to be assessed for surgery shortly. Apparently she has a diffuse cortical rather than the nuclear variety and her acuity is only modestly affected. However glare has become a big problem. Even quite peripheral car headlight are blinding. Daylight is quite complicated as matters seem to improve with a contracted pupil, but bright reflections are a particular hazard as they are unpredictable, and even a bright cloud base can severely reduce contrast. She's not a binocular user, so can't comment on how things might compare.

David

Bingo!
 
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