Last Updated on March 9, 2021
If you’re an enthusiastic outdoorsman or hunter or shooter, optical instruments are a must. You don’t see and realize your surroundings perfectly in naked eyes. Spotting scope and monocular are the types of instruments that help you viewing the objects magnified. Although their working principles are the same, their field of use is different. Don’t worry! We’re here for helping you to choose the appropriate one.
To reveal the natural beauty, you’ve to invest in a tool such as a spotting scope or monocular. Here, we’ll discuss briefly the basics of a spotting scope and monocular then their comparative discussion. We’ll also guide you through the technical information and practical examples.
Spotting Scope Vs Monocular
Before we jump into their differences and which is better in what types of conditions, let’s learn about their basic structure first.
Spotting Scope Basics
A spotting scope is a small-sized portable high powered optics that also have large apertures. It is the largest sports optics that you’ll find. Uses for spotting scope include various outdoor activities such as bird watching, ocean viewing, and other naturalist activities even astronomy. An equatorial mount for a spotting scope is a nice piece of beauty to have with you.
The other activities include hunting squirrel with good scopes, target shooting with perfect scopes, to verify a marksman’s shot placements, for tactical ranging, archery, spotting scope as telescope and surveillance. Generally, its magnification power is higher than the most binoculars and ranges from 20x to 60x.
Spotting scopes consist of some fundamental parts named objective lens, eyepiece or ocular lens, tripod mount block, dual focus wheel (knob), etc. It is set on a tripod. According to your tasks, you can choose your most suitable one from different sizes and shapes. Generally, compact ones are preferable for hiking, while a large one for hunting.
Typically, its body may be straight or angled. An angled spotting scope is preferable because you can use it in a small tripod and it also gives you a nice view up on a hill or a mountain. Hunting or target spotting and looking out of a truck on a window mount or something similar to that maybe still a better option.
So, what are the fundamental parts of a spotting scope?
Ocular Lens
The ocular lens is the nearby lens of the viewer’s eye also known as the eyepiece. Eyepieces may be adjustable to get different magnifications. For small range (20-60 yards) target-spotting, you can use fixed eyepiece scopes also. The eyepiece layout mount may be straight or angled. There is no basic difference between them, it’s a personal preference.
Objective Lens
The set of lenses that placed in front of the device is the objective lens. Its diameter is very important. The larger diameter represents more light-gathering power and resolution of a spotting scope, usually between 50 and 80mm. That’ll give you an enormously large exit pupil. So, It’s going to be bright in low-light conditions.
What Two Numbers Mean?
Spotting Scope is primarily denoted by two parameters which are magnification and objective lens diameter. For example, if you see 20-40×70 mm where 20-40 refers to the magnification and 70mm refers to objective lens diameter. A 40x magnification makes the distant object appear to be 40 times larger at the eye. Imagine, you’re viewing an elk that’s standing 120 meters apart from you through a 40-60 x 80mm spotting scope that is fixed at a magnification of 60, it will act as though it were only 2 meters apart (120 divided by 60)!
Monocular Basics
A Monocular is an optical device that works as a single tube system that is highly similar to binoculars. You can use it as a magnifying glass. In binocular you use both of your eyes while you can handle a monocular with a single eye. It produces 2-dimensional images. The name is derived from the Greek word, “mono” referring to one, and Latin “Oculus” means an eye. It is suited for rare bird watching or hunting purposes. It is lightweight so you can try it for camping, backpacking or hiking.
Monocular has some basic components such as ocular lens, objective lens, focusing mechanism, etc.
Eyepiece and Objective Lenses
Monocular is constructed with two lenses like spotting scopes. The larger objective lens diameter refers to high resolution.
Focusing Mechanism
Monocular works in a variety of different focusing systems, all with pros and cons. These include:
- Small focusing ring alongside to the eyepiece
- Small external focusing wheel near and above the monocular
- Sliding focus button
- Large knurled ring closes the objective lens
- Toggle focus mechanism on upper of the monocular
- Large knurled focusing knob nearby the body of the monocular
- Small focusing knob
- Dual focusing mechanism where there are two focusing rings
The most common type is the focusing ring around the body.
Zoom or Magnification and Field of View (FOV)
Zoom means a variable magnification facility, as often seen on binoculars, cameras, spotting scopes, or this type of optical tool. The magnification system is widely used in optical devices. Monocular has a range of magnification system. By controlling the zoom knob, you can easily get your magnification level.
Field of view (FOV) is important for being able to see a wide panorama and not appearing to be looking down a tunnel. It is related to magnification for a given situation. FOV increases with decreasing magnification and vice versa. This relationship depends on the manufacture and optical design also.
Exit Pupil
It is determined as the diameter of the objective lens divided by the magnification. So, higher the objective lens diameter and lower the magnification gives you good light admission. The exit pupil must be less than the human eye pupil.
Eye Relief
Eye relief is the distance between the viewer’s eye to the device eyepiece. Its value should be at least 10mm to 15mm.
Two Numbers Meaning
You already know what these pairs of numbers mean. If you’ve device with10x15 mm where 10 refers to the magnification and 15mm refers to objective lens diameter.
Comparison Between Spotting Scope and Monocular
Both spotting scope and monocular have some special fields of use. Sometimes spotting scope is better while at times monocular may be good. The two types of optical tools are mainly different in magnification power and lens size. From my experience, here I’m giving you a brief understanding of these two instruments.
Pros and Cons of Spotting Scopes
Pros
- High magnification (20x-60x)
- Large objective lens diameter
- Coated and multicoated lens are available
- Mostly waterproof and fog proof
- Used for longer distance ranging
- Perfect for hunting, target shooting, long-distance bird watching
- Useful in astronomy and marine
- Works as quality scope for night vision
- Multiple price range according to budget
Cons
- Time-consuming for set-up
- Portability problem for a larger one
- Need tripod to use which incurs more cost
- Higher price for higher quality
Pros and Cons of Monocular
Pros
- Easy to carry, handle and hidden
- Compact and lightweight
- No tripod needed most of the cases
- Waterproof and fog proof
- Suited for visually impaired people
- Available in different sizes
- Perfect for the short range finder and bird watching
- Handy for hikers and campers
- Best for backpacking
- Available for night vision
- Cheaper than a spotting scope
Cons
- Not sound for long-range and moving targets
- Lower magnification
Night Vision Spotting Scope Vs Monocular
Before buying any optical device you need to think first, what’s your requirement and how much your budget is. If you intend to buy night vision categories, then you’ve to pay a little more but you’ll be benefitted a lot. Once you have decided which device you need between the spotting scope and monocular you can easily avail one with night vision option. Just to be on the safe side, know the working principle of night vision first.
Before buying spotting scope or a good monocular with night vision several things you need to consider. Firstly, what type of environment will it be used in? You need to consider the remoteness you will be from the things that you want to see, as different types of monocular and spotting scope work at different distances. If you don’t need to see things in the distance, you can get away with spending a lot less on your night vision devices. Another consideration is the weather, as it can affect levels of light and visibility. Other things to consider when choosing night vision categories are discussed below:
Resolution
Night vision technology was first introduced during the Vietnam war. Since then it has evolved enormously. There are several generations on the night vision journey. They are named as Gen 1, Gen 2, and Gen 3. The Gen 3 devices are better than the other two generations. If your budget is handsome then we recommend you purchase Gen 3 devices. It’ll give you an outstanding resolution.
Magnification
Magnification is a prime factor during spotting objects, especially at night. If you want to view a steady object, then a higher magnification device is needed. You can opt for a good performing red dot magnifier for a starter. On the other hand, if your targeted object is the moving type then a lower magnification device is perfect for you. This will help you to view and realize the actual situations perfectly.
Budget
Budget is a big factor when you are going for either a spotting scope or a monocular. Like, a cheap spotting scope is readily available for you if you want, but that has some constraints too. You can also go for the budget spotting scope but, you will need some research for that. It’s really up to you. But, one thing for sure. With price comes quality.
Summary
It is hard to say which one is better, monocular, or spotting scope? It depends on where you are using them. Monocular is mostly used for short-distance viewing while spotting scope is used for relatively long-range viewing. It’s clear that according to the field of use, a spotting scope is more perfect than monocular. I hope, this guideline will help you to get your suitable one.

Kalman is a hunting expert who has a vast experience with wild game hunting. Though night time hunting is his favorite, he masters the art of daytime hunting and shooting. Being a nature lover and outdoor enthusiast, he wants to pass the knowledge acquired over time to the next generation.