Is your vision to the point where you can’t do without your glasses?
Are you tired of losing your sunglasses in the field when you take them off to glass?
In general, using binoculars with glasses should be an uneventful experience when certain binocular requirements have been met. The key features to gaining a seamless experience, whether you’re wearing prescription glasses or sunglasses, are the eye relief specifications and eyecup design.
Regardless of whether wearing glasses is out of preference or necessity, this step-by-step guide complete with tips will improve your experience.
I’ll also throw in a few binocular recommendations that fit the bill and the need.
How to Adjust Binoculars with Glasses?
1. Adjust the Eyecups (Twist or Fold Down)
Depending on the design, either twist or fold down the eyecups. Retracting the eyecups extends eye relief.
This means the distance between the ocular lenses and your eyes will be increased. This allows more room for your glasses that would normally be taken up by the eyecups.
2. Check for Full FOV Free of Vignetting
Place your eyes (with glasses on) close to the ocular lens to see if you have a full FOV (field of view) free of vignetting.
If you’re seeing black edges or rings around the FOV, this is vignetting. If possible, adjust the eyecups in small increments at a time (or to the next setting) and look for a full FOV free of vignetting.
If you’re forcing the binoculars into your face with eyecups fully retracted to acquire a collimated and full FOV, the binoculars simply do not have enough eye relief.
3. Focus the Binoculars
At this point, you would adjust for individual eye compensation by using the focus wheel and diopter to acquire a sharp image. This applies to all those who are wearing non-prescription glasses such as regular sunglasses or ballistic glasses. You will need to follow the normal binocular focusing procedure.
For those that are using prescription glasses and are therefore not relying on the binoculars to compensate for your vision, you can get glassing right away. Use the focus wheel to acquire a sharp image.
4. Repeat Process as Necessary for Different Glasses
If you use different glasses depending on the occasion, you will need to repeat this step-by-step process as necessary.
It’s not that the prescription is different between all your glasses, but the frames, lens size, distance between the lens and your eyes, etc. are going to be different. Just as you wear different shoes for various outdoor activities, your reading glasses may be very different to your prescription sunglasses.
What to Look for in Binoculars for Glasses Wearers
Best Binocular Eyecups for Glasses
There are two main types of eyecups: fold and twist. The concept behind the eyecup is to provide some level of comfort but also to keep out light. Primarily, it allows the user to acquire the correct amount of eye relief needed for a full FOV free of aberrations.
These eyecups are common on older models or very budget options. The shape can vary between models. They’re simple in design as they easily fold down (backwards) over the ocular bells of the binoculars.
If you’re consistently using glasses with binos, these eyecups aren’t too bad and will easily do the job to be out of the way.
There are two types of twist-up eyecups: preset multi-position and custom friction twist-up eyecups. Twist-ups are newer than fold-downs and are now considered the standard for eyecup design.
The preset multi-position eyecups can offer 2-3 fixed positions. Extend the eyecups all the way out if you don’t wear glasses or retract them all the way in to make room for glasses.
The custom twist-up eyecups are the ones that provide twist movement free of preset stops. As you adjust the eyecups by twisting them, they move freely both up and down. However, with downward pressure they remain in place.
Overall, twist-up eyecups are typically the better choice because they provide more flexibility for comfort and achieving a full FOV whether you’re wearing glasses or not.
Best Binocular Eye Relief for Glasses
What is eye relief? In brief, eye relief is the distance between the ocular lens and your eye that allows you to see a full FOV free of aberrations. This binocular specification varies between every binocular, and thus it is an essential spec to check before buying if one wears glasses.
Eye relief changes depending on if the eyecup is used or not being used. In essence, when the eyecups are retracted all the way, you will have maximum eye relief suitable for glasses. This “freed-up” space gives some wiggle room for your glasses.
When the eyecups are fully extended, eye relief is at its minimum. The eyecups are taking up more space that results in a tighter fit to comfortably use with glasses on.
When checking eye relief specs, look for the maximum amount of eye relief listed by the manufacturer. The higher it is, the better.
How Much Eye Relief Do You Need?
On average, 15-16mm is the unofficial minimum eye relief for glasses wearers. Those who don’t wear glasses can work with as little as 11-13mm, though comfort level would be questionable.
Generally, 18mm is adequate to acquire an unobstructed FOV, though 20mm is even better though harder to find.
Best Binoculars for Glasses Wearers
|Max. Eye Relief
|Bushnell H20 10x42
|Maven C.1 8x42
|Leupold BX-4 Pro Guide HD 10x50
|Swarovski 8.5x42 EL
Can You Use Binoculars Without Glasses?
Overall, binoculars can be successfully used without glasses for vision conditions such as hyperopia (farsightedness) and myopia (nearsightedness). Most binoculars will have a diopter with a correction range of -5 to +5 approximately to compensate for this.
For other visual conditions such as astigmatism, it is recommended to wear your glasses while using binoculars to acquire maximum image quality, i.e., sharpness, resolution, clarity, etc.
The caveat is to look for key binocular features that can improve your experience for maximum comfort and glassing quality, i.e., long eye relief and quality eyecups.
Whether you’re sporting shades or if it’s out of a visual necessity to wear your specs, there’s no reason you shouldn’t be able to wear them without compromise - if you know what to look for in binoculars!