I had a bit of a disturbing moment today as I was out with my FL's. The day was overcast but the sky was quite bright. For the 1st time since owning these bins. I noticed what looked to be chromatic abberation....strong orange fringing to backlit objects.
I did seperate barrel tests and it was clear that the left barrel was the culprit, the right was perfectly clean. I did a comparison with my older Elite's and the left barrel showed worse than even the much older and less sophisticated model.
Aghast, I was straight on the phone to my dealer to describe the problem. He thought it very unusual and suggested the following....try each eye in each barrel and check the results. Well, to my surprise, it is my left eye that is producing the effect, not the binocular, as I could see abberation in both barrels with the left eye and clean results with the right.
I double checked in my Elite's and, while both barrels showed some, it was consistantly worse with my left eye.
Has anyone else encountered this problem? Is there a remedy [apart from wearing glasses, which I do not] and does anyone know the cause of abberation in one eye and not the other?
Sometimes, when an edge within the image is out of focus, and there is much contrast, it seems the CA is more visible than it is when the focus is perfect.
If you have astigmatism, my advice for you is to wear spectacles, and if you don't, be sure that the diopter setting is accurate for your vision.
You should also try to find out if you can see the CA with your unaided eyes. You have to produce a situation similar to the image in the binoculars, like the edge of a roof against a bright, overcast sky.
Remember, the binoculars only magnify what you see, they cannot provide miracles. If your left eye is worse and beyond real improvement with spectacles, the binoculars will not be better than your eye.
The nature of the eye's aberrations (and they are vast) is not yet fully known, especially not for individuals.
Some years ago there was a hype about wavefront corrected, custom made contact lenses, but that track has been abandoned, AFAIK.
The contacts would, in theory, be able to produce superhuman visual acuity, but the contact lens itself would be the weak link, as its surface would deteriorate from deposits, and while immobility of the contact lens would be optically desirable, it would be harmful to the corneae.
Possibly, a second wave (!) of wavefront correction will come in the future, but then with spectacle lenses.
However, one of the worst sources of optical imperfection is the cornea. Techniques that modify its surface structure by overnight wear of custom made rigid lenses (where myopia is absent during the day) will increase the visual acuity to 30/20 or even 40/20 for some individuals.
Aberrations emanating from deeper within the eye (especially the lens crystallina, but also the vitreous body) will not show any improvement from corneal surface modification.
If you haven't seen your optometrist for a long time, you should go see him/her, and make sure your intraocular pressure is measured too.