Should I wear my glasses when using binoculars?
Binoculars are primarily used to bring a far-away image closer through a magnification mechanism. It has a built-in focal adjustment that both near- and far-sighted individuals may be able to adjust without the use of their glasses. It worth noting that the distance between the eyeball and the eyepiece lenses is wider for those wearing glasses, which can affect focus ability. There are several factors to consider when deciding if wearing your glasses is the best option.
Astigmatism is a condition where the cornea is egg-shaped rather than spherical or round. Therefore, the eyes will not focus in the right way, and instead, the reflection hitting the eyes will be focused on the retina in two parts. Therefore, individuals with astigmatism will need to keep their glasses on while using the binoculars.
Glasses with a thinner frame may interfere less with a field of view. Larger lenses will accommodate the binoculars eyecups better by helping to reduce the amount of ambient light that comes through the eyepiece.
Eye relief is the distance between your eyes and the eyepiece lenses. It makes it possible to have a full field of view with or without the glasses. An entire field of view is achieved by simply fine-tuning the eye cups. Those who use glasses should use binoculars with 15mm or greater eye relief to compensate for the extra distance eyeglasses create between your eye and the eye cups.
Size of the exit pupil
The amount of light binoculars can allow into the field of vision is the exit pupil size. Users who need to keep their glasses on while using binoculars will likely need a larger diameter exit pupil, as the distance from the eye cups can interfere with how much light is detected by your eyes. As such, the image will appear dimmer.
Magnification in binoculars follows the same principle that applies to eyeglasses. They come with different magnifications depending on prescription and design. For users who require glasses to see long distances, lower-level magnification may require keeping your glasses on. Higher-powered binoculars may afford you the opportunity to remove your glasses and still see the image clearly.
Eyeglasses lens coating
Sometimes anti-glare or anti-scratch coatings applied to eyeglass lenses can interfere with binocular viewing. For example, transition lenses that get lighter or darker may react while using binoculars and obstruct your view.
Eyeglasses won’t necessary impede your use of binoculars, especially if you keep these factors in mind. The best way to test whether your glasses interfere with binocular use is to try a few different models in varying light conditions.