There was no gain or increase in FOV when dialing down in power from 7-5x.  This indicates that neither the magnification or FOV are directly proportional in this case.  The scope is no longer a true 5-20x scope, it's now a 7-20x scope.

Tunneling is usually noticed and experienced with rifle scopes, although other zoom/variable power optics can have this malfunction.  Tunneling is when the field of view does not increase or decrease when you change magnification.

When you dial back down to low magnification, the field of view will become wider as you see more of the surroundings in your view. Notice the change in field of view looking through my scope at 5x compared to 15x magnification:

Pentaprism is a five-sided reflection prism with four active surfaces, which has an unique ability to reflects light at 90 degrees independent of the incidence ...

Bandcamp · Other Doors · Live at the Baked Potato · Hidden Details (HD) · Burden Of Proof Soft Machine Legacy · Live Adventures Soft Machine Legacy · Steam Soft ...

If a binocular says it has FOV of 341 feet at 1000 yards, it means you can see 341 feet of a scene from left to right when looking at 1000 yards.  Measurements in feet, meters, and yards are called the linear field of view.

NeewerRing Light

While some scopes tend to have this issue at lower magnifications, it can happen across the entire magnification range, and some power levels may be worse than others.

Note: Camera, light stand and strobe flash NOT included. All products from this link are original                   TRIOPO, sometimes the products may not be printed LOGO due to producing schedule, but             they are also from TRIOPO.

20211213 — Basler AG. The first provider on our list is Basler AG. · Allied Vision Technologies · Cognex Corporation · Hamamatsu Photonics K.K · Teledyne DALSA.

The Triopo Lantern is one of the fastest soft light modifiers, it's constructed with collapsible nylon diffuser cover and lightweight foldable iron frame shaft, it can be conveniently set up or packed up in seconds by controlling through the shaft lock.Comes with a black carrying bag, makes your storage and transportation much easier. As filmmakers, you need to move fast, and your lighting shouldn't get in your way. With the lantern you'll be able to produce soft even light wherever you shoots.

The Lantern is the perfect photo or video accessory for casting soft light over a wide area, while still maintaining control and without glare. It can modify any Bowens mount light into a Chinese lantern orb - The perfect solution from architectural to event photography.

For example, the rangefinder with 6.0° FOV x 52.5 equals 315 feet at 1000 yards.  This is because one angle degree is equal to 52.5 feet.

Ring light diffuserDIY

Amazon neewerRing Light

What Is a Wide-Angle Lens? ... Wide-angle lenses are lenses with an equivalent focal length of between 24mm and 35mm. They offer a wide angle of view that makes ...

Ext. (Extension). This field refers to an extension, if any, for the given telephone number.

We promised to give you the plain view of the field of view without any fancy fluff.  There you have it.  It was easy enough, right?

Hi Greg. The FOV is determined by the magnification of an optic and other factors but not the objective lenses. Generally, larger objective lenses tend to be paired with higher magnification, and this usually results in a narrower FOV. However, it varies between manufacturers and even between models from the same manufacturer. Take for example Maven's 10x56 binos with a 341 FOV and their 10x30 with a 341 FOV. They're the same even though the objectives are significantly different in size. This example is not a rule by which to govern binocular FOV by. Changing the objective lens won't change the FOV as the FOV is proportional to the magnification. I hope that answers your question. Thanks!

FOV is provided by manufacturers in multiple measurements.  Binoculars, rangefinders, and spotting scopes tend to measure FOV in feet at 1000 yards.  Rifle scopes provide FOV in feet at 100 yards.

Yes, almost every feature on an optic has to do with the mechanisms of another feature.  So, how does magnification affect field of view?

Just happened on to your FOV explanation. Simple and clear but I think you made a typo, one degree angle at 1000 yards will be 62.5 ft linearly, not 52.5. You had me scratching my head for a second (of time, not angle).

RingCameralightCover

La lunghezza focale é la distanza ( in millimetri ) ... esempio di focale fissa é il 50mm). ​. Gli Zoom ... Esempi comuni sono il Nikon e Canon 85 mm.

The rule is simple.  Increase magnification, decrease field of view.  When you crank up the power on your scope, you're going to see less of an area as you get more specific detail on your target or scene.

DimmableRing Light

Bad ground. Your tail lamp power is going through that filament, but can't get to chassis ground (yet). What is happening is your tail lamp filament is grounded ...

Field of view (FOV) is the measured area of the scene you can see when looking through your optic.  It is determined by multiple components in the optic that includes the eyepiece, thickness of the lenses, position in its assembly, and magnification.

Ha! I appreciate the pun. I'm no math whizz, but there are other formulas by which to calculate FOV, but the most common one that I've found that provides a great approximate from degrees to linear feet is the 52.5 constant. Now why we use 52.5 - I'm not exactly sure. I've heard that it's because it's easier to remember than 52.36519478... maybe?

With the ability to fit onto any Bowens mount supported flash speedlites, studio strobe or LED fixture, such as the Godox SL-60W SL150W II FV150 AD300PRO AD400PRO AD600BM VL150 VL300 SL150WII SL200WII series lights, Aputure 300D II 120D, Neewer SL60W SLB60W HY-1000Li SL-150W SL-200W continuous Led Light and Other Bowens Mount strobes and monolights.

By utilizing a 55cm/65cm/85cm spherical structure design, the Lantern softbox spreads the light from your LED lights or Studio Strobe/monolights by casting 360° beam angle even and omnidirectionallighting to soften the light for small rooms or an entire larger space, creates a soft natural lighting or accent lighting effect that is great for revealing the gradual skin tone in portraits, no shadows, not dazzing, making the skin extremely delicate, adds more life to your subject. ideal for portraits,commercials,Microfilm production, video recording, children shooting, live streaming, overhead photography,cinematography and film-making.

Sometimes, you'll see FOV provided in angular degrees.  A rangefinder may have an angular FOV of 6.0°.  The higher the angle, the wider the field of view, and the angular FOV remains the same at any given distance.  To calculate angular to linear FOV is easy.  Multiply the angle by 52.5 to get the linear feet FOV.

Can you be sure what scopes have tunneling issues before you buy?  No manufacturer I'm aware of advertises tunneling as a feature, benefit, or advantage.

2004728 — They don't work on the left eye, but the vision in the right's better so the combination of left lens / pinholes works better than anything else ...

As there are many structural and design elements that govern FOV, we'll just leave that to the manufacturer, but we can master the numbers, so we know what we're getting or what we're missing out on when buying a sport optic.

This was a great article and you explained some phenomena with which I have occasionally been troubled but now understand better. Thanks much for the information!

There are clear quality differences which depend massively on the glasses used, the lens coatings and the entire optic design. Particularly optical errors like ...

Knowing the Field Of View (FOV) may be important for what you want to do.  If it's birdwatching, a wide field of view will make it easier to track moving birds.  If it's sub-500-yard hunting, standard rifle scope FOVs will work just fine.

Constructed with collapsible nylon cover, 12pcs iron rods supports and lightweight foldablealuminium shaft, sealed with Velcro to prevent light leakage. The silver-grained reflective cloth design also better reflects the light source and is more heat-resistant, the stainless steel frame is tough and durable.

For example, on a 5-20x rifle scope, the Field Of View (FOV) should be larger at 5x than it would be at 7x.  When you increase magnification, you lose FOV.  When you lower magnification, you increase field of view.  However, when experiencing tunneling, the FOV would stay exactly the same at 7x as it is at 5x.

Ring LightSoftbox

Other times, additional components have been added to an optics assembly to compensate for lens and coating defects and to minimize chromatic aberration and lens distortion.  However, these additional components in the optical path can cause tunneling.

The buying process is a perfect example of doing some purposeful digging and research before you buy.  Reading the rifle scope reviews, checking in with the masses, and doing your homework will go a long way.

7.4 x 52.5= 388.5 feet/1000 yards - off by .5, so it's a great approximate but using the 52.36519478 number would be exact.

If you're too close or too far outside of the given eye relief distance, your view of the surroundings through your optic is going to be affected.  You may see the Field Of View (FOV) slightly blocked out or part of the FOV is "clipped."  This is called vignetting.

Sometimes being too far out of the given eye relief distance might cause a shadowing or ring of vignetting around the entire edge of the FOV.  You will want to get your eyes within the eye box (within given eye relief specs) to ensure you have a clear and unobstructed Field Of View (FOV).

2024521 — Importance of PCB Inspection in Manufacturing · Solder Joint Defects: Poor solder joints can lead to intermittent connections or complete ...