Understanding FOV (field of view) and other features of your rifle scope setting helped level up my accuracy and marksmanship.
Thanks to modern scope technology and a more sophisticated lens system, there’s never been a better time to be a hunter or a bird watcher than now!
Do you want to understand what field of view is without getting too technical about it?
I’ll try to break it down for you with less scientific stuff that usually comes with the study of scopes and optics.
Contents
What Is Field of View (FOV) and What Does It Mean?
Field of view is the measured area of the scene when you look through the scope from right to left.
In other words, it’s how much of the surroundings you can see through the scope.
The FOV is affected when you change the scope magnification.
If I put my scope on the lowest magnification setting, my field of view is HIGHER because I can see pretty much all of what the scope covers.
However, if I ZOOM IN on a target (like an animal), the field of view becomes SMALLER because the scope sees that target only and nothing else.
I realized that it’s similar to a camera! You see MORE when you zoom out and LESS when you zoom in.
Why is field of view important, you may ask?
This is because you want to be on the lookout for the tunneling effect, which is NOT a favorable occurrence when using rifle scopes.
The tunneling effect is when the field of view does not increase or decrease when you change the magnification.
To elaborate, what you see on the riflescope is like a tunnel. It remains the SAME even when magnification adjustments are made.
This can only mean that your scope is not high quality and will not be good for your aim.
When using two different rifle scopes, it is important to note that the field of view may still vary.
There are several factors that affect FOV in a rifle scope.
It could be the…
- Thickness
- Contour or shape of the optic
- Scope tube diameter
- Magnification
Magnification Explained
Even if you’re new to how riflescopes work, this isn’t so difficult to understand.
Magnification is how much closer an object appears to be compared to what the naked eye sees.
If the manufacturer says the scope has a 4x magnification, it means that the target will look 4 times closer than what the eye sees under normal conditions.
Magnification is important in rifle scopes because it helps you see a far-away target better!
I used to think that a high magnification always gives you a crisp and clear image, but that’s a common misconception.
This is NOT necessarily the case because it will depend on the intended scope magnification use.
Factors like distance to the target and type of range, whether open or closed, are taken into consideration.
There are no set rules when it comes to magnification, even with the commonly found configuration of your rifle scope.
I use these magnifications as a general guide when shooting with scopes.
- Up to 100 yards – 1-4x
- Up to 200 yards or closed landscapes – Between 5-8x
- Beyond 200 yards or hunting in open areas – Use magnification between 9-12x.
How Does Field of View Affect Rifle Scopes?
So, how does magnification affect the field of view? Their inverse relationship is simple.
Increase magnification → decrease field of view
It’s quite self-explanatory.
When you INCREASE the zoom level of the scope, you see more accurate details of the target, but you end up seeing less of the scene.
Meanwhile, the field of view will become WIDER when you adjust your scope to a LOW magnification.
As a result, the surroundings appear bigger in your view.
For example, a 3x scope will have a FOV of 30 feet at 100 yards versus a 9x scope having only 14.
Even if you have a larger objective lens diameter, it will remain as is. But achieving the perfect magnification scope setting is NOT an easy feat.
Similar scopes will not have the same FOV at the same level of magnification.
Sometimes, it can come down to the manufacturer of the scope!
Other Factors that May Affect Field of View in a Rifle Scope
Eye Relief
Any optic with an eyepiece requires adequate eye relief.
This refers to the distance between the scope’s ocular optic and your eye to see an unobstructed image of your target.
You’ll know that it is adequate because of the level of COMFORT it gives your eye to see the WHOLE FOV.
I prefer a long eye relief scope as it allows for a more natural shooting position.
My recommended amount of eye relief is around 3.5 – 4 inches.
Exit Pupil
The power of scopes is also affected by the exit pupil. It refers to the diameter of the light beam that passes through the scope to the eye.
If your scope has a smaller exit pupil, it is more focused, which is why higher magnification almost always comes with a lower diameter.
In my experience, it was useful in dark, cloudy weather or when I am shooting at night.
What FOV & Magnification Is Ideal for My Rifle Scope for Hunting?
I mentioned earlier that as the magnification increases, the field of view becomes narrower.
So what determines the field of view?
I found that it’s more helpful to have a WIDE field of view and LOWER magnification when hunting moving targets.
Meanwhile, precision long-range shooting is easier with a SMALLER field of view and HIGHER magnification.
REMEMBER: Magnification always plays a part and determines FOV.
Remember that when you have a smaller FOV, you CAN’T see what’s going on in the surroundings and potentially lose an opportunity.
I recommend a VARIABLE scope with lower magnification.
Aside from magnification, the field of view is also related to the construction of the eyepiece and the scope.
Let’s understand some concepts behind the parts of a rifle scope.
Objective Lenses
A rifle scope has two ends.
The objective lens is the one located at the end of the scope. This is the larger objective lens that is nearest the target.
It is responsible for sending any light transmission back to the ocular optic (the one closest to the eye) and, therefore, achieves a BRIGHTER image.
The section containing the ocular optic is the eyepiece.
If you want to know the objective lens diameter of your rifle scope, look for the number after the “X” in the scope title.
For example, in a 3-9x30mm rifle scope, the objective lens diameter is 30 millimeters. It refers to the focal length of the optic.
The typical objective lens diameter ranges from 20-56mm.
Scope Tube
The main body of the rifle scope is the scope tube. There are various tube sizes from 1″, 30mm, or 34mm.
Rifle scope tube size is based on the internal components of a scope.
It is relevant to be aware of the scope’s diameter to match it with the proper scope rings needed when attaching the scope to your rifle.
Scopes also have a reticle, also known as a crosshair. These very thin markers reflect exactly where the shot will go.
With the right magnification and the scope’s reticle focused, a good aim is almost within reach!
Fixed vs. Variable Scope
Fixed rifle scopes are single magnification scopes, meaning they only have one number (for example, 3x).
In comparison, variable power scopes have more than one magnification (3-6x).
A fixed power scope makes you aim faster and probably costs much less than a variable power scope.
But the setback is it only has one magnification and is, therefore, suitable if you plan on shooting from one distance or target range only.
Get a variable scope if you plan to use a rifle scope in different kinds of environments and situations.
I like using variable scopes as they give me more flexibility when it comes to utility.
Frequently Asked Questions
How Is the Field of View Measured?
There are varying measurements for field of view depending on the type of scope. Field of view is expressed in two ways.
- When the field of view is expressed in feet, it is called the linear field of view.
- When it is shown in degrees, it is referred to as angular.
Binoculars, rangefinders, and spotting scopes typically measure the field of view in feet at 1000 yards.
For rifle scopes, the field of view is measured in feet at 100 yards.
What Does FOV at 100 Yards Mean?
The field of view for scopes is standardized at 100 yards, meaning the width of the field of view if you were to measure it is 100 yards away.
Most hunters only use between 50 – 150 yards and do not require a very high magnification range.
A common question is whether a large or small FOV is needed to get a clear shot.
Look at it this way, a wider field of view shows you a larger area and allows you to aim more accurately at the target.
For rifle scopes, a 1x- 2.5x magnification is sufficient already.
However, when aiming your scope at a dangerous game, the magnification range can be stretched up to 150 yards for safety considerations.
Is Field of View Always Measured at 100 Yards?
For rifle scopes, yes.
100 yards is the standard distance which hunters use when measuring field of view.
Fore example, binoculars measure the field of view at 1000 yards since they are used for farther targets.
What Does FOV at 1000 Yards Mean?
Field of view at 1000 yards is for binoculars and other scopes used for spotting game.
It is farther than scopes because the main purpose of binoculars is to enlarge a scenery by way of magnification.
The width of the field viewed from 1000 yards away makes it possible to focus on a target, evaluate a terrain, or simply appreciate nature!
As earlier mentioned, field of view is a product of the diameter of the objective lens in relation to magnification, among other factors.
The same principle applies to the field of view of binoculars and spotting scopes at 1000 yards.
The higher the magnification, the less field of view.
Do You Need a Large or Small FOV?
It depends on your purpose.
A SMALLER field of view is useful for when you are shooting with a long range scope with higher magnification.
Meanwhile, a LARGE field of view is best for moving targets.
In my experience, I zoomed in too much on a little squirrel. Next thing I knew, it disappeared from my line of sight as it ran away.
If the field of view is smaller, once these targets move, they will be out of the line of sight of your scope, making it more difficult to track them.
Know Your Purpose
If you are looking to buy one or scouting for a more sophisticated lens system, it would be prudent to evaluate the purpose of your rifle scope.
To help you, I listed some questions that will help you build a checklist:
- What will be the primary use of the scope?
- What is your budget?
- Where do you plan to use the rifle scope?
- What kind of lighting conditions are you expecting?
- What are the weight limitations?
- What is the preferred size of your target in relation to your scope?
- What are the expected weather conditions?
Before jumping the gun, be aware of the rifle scope specifications in the market.
Based on your answers to the above questions, hopefully, you will find the perfect rifle scope for you, one that hits the spot!
PRO TIP: Start with the most commonly found configuration and work your way from there. See how the scope feels, understand the ranges, and don’t forget to gauge eye comfort and natural posture when you aim.
Final Words
I hope you were able to better understand FOV, and through this article, your knowledge about different scopes increased!
Even though field of view is super easy to understand, it is something that you cannot overlook.
Knowing the right magnification and field of view will eventually lead you to a better and more precise shooting session!