8 Interesting Facts About Binoculars
Binoculars are a tool that lets you see things ‘though you’re far away. They are made up of two similar telescopes mounted together – one for each eye.
Binoculars have become essential not only for going outdoors but even as a household item.
If you’re looking into buying a pair of binoculars, here are some facts about binoculars you’ll want to know as a backgrounder.
Here are some fun facts about binoculars:
1 – The Two Numbers Tell You the Magnification and Diameter
Usually, the first spec they tell you about binoculars is this: 7×50, 8×40, or 10×35.
The first number is the magnification power. It tells you how many times the object is magnified. So, in 7×50, the object is magnified seven times.
The second number refers to the aperture or diameter of the reflective lens (front lens) in mm. The larger the aperture, the better images you’ll get. But keep it within 50mm.
2 – 10x Magnification Max
10x magnification is the most magnification a person can hold steadily.
If it’s higher than that, you’ll have shaky images. You’ll need a tripod.
3 – Focussing – Turning the Knobs
Focus or image point is where the light rays come together. It comes as a spot which they call the blur circle.
Each telescope or each side has an independent focussing.
4 – Eye Relief Matters for Eyeglass Wearers
Eye relief is the distance from the outermost part of the eyepiece lens to the eyepoint or your exit pupil.
If you’re wearing eyeglasses and the eye relief is too short, you won’t be able to see the whole image. You’ll only see the middle part of the image. Or you’ll see a black shade around the image (vignetting).
Experts recommend eyeglass wearers to use binoculars with a longer eye relief.
5 – What is Range Finding?
Many binoculars come with a range-finding feature.
They use a range-finding scale allowing you to measure the distance between you and your object of focus efficiently.
6 – Stabilized Binoculars for Shaky Hands
Shaky hands make viewing images through optics challenging. And tripods can be bulky to bring around.
The good news is, there are stabilized binoculars. Aside from having shaky hands, stabilized binoculars are ideal for using when you’re in a moving vehicle or a boat.
7 – Coatings Matter
When light passes through air to glass, a small percentage of light is lost. And light has to go through several glasses before it reaches your eyes: main lenses, prism, and eyepieces.
With coating, it can bring down the percentage of light that’s lost. Experts advise bluish, greenish, or purple-ish colors make good coatings.
8 – Roof Versus Porro Prism Binoculars
These are the two major types of binoculars. Although they both serve the same function, there are many differences between them.
Binoculars use prisms to correct the image orientation of the object. The image formed by the objective lenses appears upside down.
This is where prisms come in. Prism technology turns the image so you can view it with the right side up.
Porro Prism Binoculars:
Porro prism binoculars have a classic, vintage look. They were the only type of binoculars until roof prism binoculars were introduced in the 1960s.
Their eyepieces are closer to each other than their objective lenses.
Porro prism binoculars are generally cheaper than roof prism binoculars. But they can give you the same quality of images. Some argue Porro binoculars can give higher quality images.
However, they are heavier and can be lacking in modern features such as weatherproofing.
Roof Prism Binoculars:
Roof prism binoculars have two straight tubes. This is what makes them more compact and lightweight than Porro prism binoculars.
Roof prism binoculars look simple. But their prism technology is more complicated. Roof binoculars are the better option when going on adventures because they’re lightweight, most models are fog-and-waterproof, and they’re more durable.