How To Choose Binoculars For Short Sighted People (Best UK Guide)

If you are one of the 33% of UK residents that suffer from myopia ^[1] (short sightedness) and using binoculars without your glasses is impossible, read on for the best solutions to this very common problem. 

Most modern binoculars have eye cups that can be adjusted either by twisting or rolling them down (this depends on the brand, some have twist eyecups others have rubber eyecups that can be folded manually).

Binoculars For Short-Sighted People That Don’t Want To Wear Glasses

If you suffer with myopia and do not want to wear glasses when using binoculars, there is always the option of contact lenses. Some people find contact lenses to be uncomfortable, and if you are one of these people, it is possible to buy binoculars with a graduated dioptre range. The majority of these will only have a range of +/- 4 dioptres, which will probably not be wide enough to cater for glasses.

There are some with a wider dioptre range but they can be very expensive. A pair of binoculars with a dioptre range of +/- 7 dioptres will cost somewhere in the region of £600 to £800. Where a similar pair with all of the other specs apart from the higher range dioptre will cost around £150 to £250 with a lifetime warranty. So maybe buy a pair with long eye relief to accommodate your glasses.

Also the dioptre range is for compensating from one eye to the other and will not necessarily account for the wearing of glasses. It will be far better (and cheaper) to buy binoculars with long eye relief.

What Is Long Eye Relief?

To answer this fully, let’s explain what eye relief is first. Eye relief is the distance between your eye and the binocular lens where you can still see the full image through the lens of the binoculars. This is usually quoted in the specs for each pair of binoculars in millimeters and the average eye relief is anywhere between 12 to 16 mm.

Long eye relief is anywhere above 16 mm and usually up to 24 mm. This allows enough room for those of us that wear glasses to keep them on and still see the full image through the lens of the binoculars. If your glasses are not too large, you might get away with 15mm but it’s better to have too much eye relief as this can be adjusted down, whereas there is a limit to how far an upward adjustment can be made.

It’s worth trying the binoculars without your glasses especially if your myopia isn’t too bad. This is because most binoculars allow adjustments of +/- 4 dioptres. However for under £300.00 you can buy the Hawke Frontier HD X 8×42 binoculars with a long eye relief of 18mm, a field of view of 8.1°, twist up eyecups fully multi-coated lens coatings, BAK4 prisms with dielectric coatings, waterproof and fog proof, complete with the Hawke lifetime warranty.

What Does Field Of View Mean?

The field of view (FoV) is the area you can see through the lens of the binoculars from left to right while looking straight ahead. The recommended FoV is between 6° to 8° or 105 metres per 1,000 metres to 140 metres per 1,000 metres. Which means at 1,000 metres you’ll be able to see a width of 105 metres to 140 metres respectively.

The FoV is important because it can mean the difference between seeing an object like a rare bird for example or it flying away before you can focus on it. This is because with a wide FoV you can see a larger area without having to remove the binoculars, finding the bird again and repositioning the binoculars.

What Do The Numbers Mean?

We spoke earlier about the Hawke binoculars with an 8×42, these numbers refer to the level of magnification and the objective lens size. Both of these numbers are extremely important when buying binoculars because they tell you how far you can see and how bright you can expect the image to be.

8x represents 8 times magnification, which means that you’ll be able to see an object 8 times larger through the lens than with the naked eye. Any binoculars above 10x magnification will show any slight shake we have when holding heavy (ish) objects for long periods. Any higher than 10x will need a tripod to keep them hands free and prevent a blurry image.

The last numbers are the diameter in millimeters of the objective lens.

The objective lens is the one closest to the object you are looking at (the larger lens of the 2), and in this case is 42 mm in diameter. The size of the objective lens is important because not only does it tell us the size of the binoculars but it also allows light to gather in the binoculars which brightens the image you see through the lens.

Binocular Sizes

As we just said, the objective lens tells us the size of the binoculars, which come in 3 sizes which are;

• Compact – Objective lens diameter below 30mm
• Mid Size – Objective lens diameter of between 30 to 40mm
• Full Size – Objective lens of greater than 40mm

Just because a pair of binoculars is considered full size because the objective lens diameter is greater than 40mm doesn’t mean they will necessarily be a massive pair of binoculars. That’s because there are two types of binoculars and one is far bigger than the other.

Types Of Binoculars

Regardless of the size classification, there are two types of binoculars which are easy to distinguish between because of their totally different shapes. They are;

Porro Prism Binoculars

Porro prisms are that classic M shape binocular and are the larger of the two types. They have two offset prisms in each lens which accounts for their bulky midsection. They are larger, heavier, bulkier, more difficult to fully waterproof, easier to damage, but cost less than roof prism binoculars.

Roof Prism Binoculars

These are shaped like a H and are decidedly smaller than Porros, because as the name suggests the prisms are set in the roof of each lens. This allows them to be smaller, lighter, and more compact than Porros. They are also easier to fully waterproof and as the prisms are mounted in the roof of the lens tubes, less likely to get damaged.

If Porro prism binoculars get a slight knock it is possible to misalign the prisms. This misalignment will lead to eye strain, headaches and migraines if undetected. Roof prisms cannot get knocked out of alignment because they are made in a different way.

What Does BAK4 Prisms Mean?

The Hawke binoculars we mentioned earlier have BAK4 prisms, this refers to the grade of precision optical glass the prisms are manufactured from. BAK4 is the top quality optical glass with the least imperfections which means you will see a clearer brighter image.

There is another, lower optical glass used in the manufacture of prisms, BK7 prisms are still high quality precision optical glass, but with slightly more imperfections than BAK4. Both will provide you with great images but BAK4 is the best quality. The dielectric coatings refer to the roof prism coatings that are actually called P-coatings.

What Are P-Coatings?

The P stands for phase, what happens with roof prism binoculars is the light gets bent and split into two as it passes through to the lens, which can cause the image to be out of phase. The manufacturers have found a way to combat this phasing by coating the prisms in three different ways. The dielectric coating is the best of the best which means the image you see through the binoculars will be completely in phase, making it clear and bright.

What Does Fully Multi-Coated Mean?

The actual lens you view through gets coated to prevent glare and improve the image quality. There are many different coatings available but fully multi-coated means every piece of glass has been coated (inside and out) with multiple layers of glare reducing, image brightening coatings.

Waterproofing & Fog Proofing

It’s always best to go for waterproof binoculars because once moisture gets inside the lens tubes you will never get a perfectly clear image again. Now as there are many different claims for waterproofing binoculars like “weatherproof” and “water resistant”, the industry developed their own code to distinguish just how waterproof they actually are.

This industry coding can be slightly confusing but suffice it to say that an IPX6 code will be more than sufficient for anything the British weather is likely to throw at you. With IPX7 meaning the binoculars could spend up to 30 minutes submerged in a metre of water without any water seeping inside the lens tubes.

To make binoculars fog proof they remove all of the air from the lens tubes and replace it with a gas (usually nitrogen) that contains no moisture. This means it cannot react with any rapid changes in temperature and fog up. As this gas is sealed in, nothing can enter either, which means the binoculars are also dust proof too.

Protective Casing

All of the top quality binocular brands wrap their binoculars in a protective casing of either rubber or polycarbonate to prevent any accidental damage. It’s easy to either drop binoculars or just bash them on a rock or concrete fence post which could cause some damage to the body. That’s why they are protected, but the coating also prevents them from slipping from wet hands too.

Warranty

All decent binoculars will offer a warranty of some kind, as you’d expect from something costing north of £200.00. The top quality brands offer a limited lifetime warranty, which means as long as they are owned by the original purchaser, they are guaranteed against accidental damage. Which basically means as long as you don’t deliberately damage them they will be repaired or replaced free of charge by the manufacturer.

Frequently Asked Questions