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Can a binocular have too big of a FOV? (1 Viewer)

[email protected]

Well-known member
Supporter
After having the new Swarovski NL 8x42 it made question if there is a limit to how big of a FOV is actually usable. When I would pan with the NL I actually had to look around the FOV to make sure I didn't miss a bird because it is so big but with an 8 degree FOV binocular I can actually pan faster because I can almost immediately see the entire FOV. With the NL I found it difficult to take the whole FOV in at once like I can with a normal sized FOV. Do you think there is a limit to the size of the FOV or should manufacturers keep trying to make the FOV larger and larger?
 

sillyak

Well-known member
Once you get to a point, maybe somewhere around 65° AFOV (simple method), I don't think it serves a practical purpose, but it does certainly add immersion. Whether or not it slows down a search would depend on the individual I'm sure.

I find 100° AFOV eyepieces amazing for astronomy; however in astronomy, you are sometimes trying to fit an object in a certain FOV. You never have an issue with a bird not fitting in the FOV of binoculars.

I think they should keep pushing the FOV wider. Eventually there is a point, you can only go so wide and still fit the form factor of binoculars useful in the field.
 

[email protected]

Well-known member
Supporter
That is true about astronomy. I have used the ultrawide FOV Nagler eyepieces but in astronomy you are not dealing with something that is moving very fast out of the FOV like a bird. You have time to sit and examine the FOV clear to the edge if you have a clock drive that compensates for the earths movement.
 

WimDel

Active member
No. I like the immersion, like you are there in front of the bird and forget you are looking through binoculars. I never liked the tunnelvision you get with <60° AFOV. That’s why I like my NL 10x so much. And I have no difficulties seeing the whole FOV while panning.
 

jring

Well-known member
Hi,

in my opinion the limit of usefulness for afov is somewhere near 80 deg because that is what I can see without doing strange eye gymnastics.

I do own a 9mm ES 100 deg EP but in hindsight I would be fine with 82 deg (like my other EPs). Might be different for use with glasses as these astro EPs often don't have a lot of ER and an EP with 100 deg nominal might still give around 80 with glasses...

Some people seem to prefer to see a certain amount of field stop for daylight observation, so sth in the 65 to 70 deg afov range would be just right. So the NL with their 70 deg afov should be just right.

Joachim
 

yarrellii

Well-known member
Supporter
Then there's the question of facial features that can actually negate the actual use of a super wide FOV. I opened a thread a while ago regarding this issue, where I explained that in my case, probably due to my facial features, I simply can't make use of the FOV of most wide angle binoculars. It's here, some forum members raised very interesting points.
As an example, just today, a few minutes ago I've received a 6.5x32 Levenhuk Sherman Pro. It says 10º FOV but according to Allbinos and other sources it's only 9,1º... and again, I was unable to see the field stop in a "natural and comfortable" viewing position, even if I pulled the eyecups all the way down (I don't wear glasses). I get the same thing when AFOV starts to go beyond 60º and approaches 65º and beyond. I can't see the entire FOV in a EII 8x30 or most other WA I've tried. So in my case, a superwide FOV is less and less important. Eyecups with many intermediate positions are a plus, and finding the perfect fit/match with a particular device is the optical nirvana ;) Something between 60 and 65º does it for me.
 

Troubador

Moderator
Staff member
Supporter
I am a big fan of large fields of view, not because I am looking for immersion and not to look around the edge while holding the binos stationary. When I am panning the binos to scan sky for raptors or open water for re-surfacing water birds or dolphins and other cetaceans or otters, I only need to see an object as I pan and then I can centre that object in the fov and examine it. A bigger fov allows me to scan big areas more quickly and I am struggling to imagine why there should be a limit to the size of the fov. For much of my searching I am using peripheral vision to spot something interesting.

Lee
 

Foss

Well-known member
I agree with Sillyak that they should keep pushing. A 1940s SARD 6x42 has nearly 12° FOV, is extremely immersive, and offers a most enjoyable view, though not a birding binocular in any way, shape, or form. Eighty years later, I don't doubt there wide-field improvements to be made.
Jack
 

[email protected]

Well-known member
Supporter
On a binocular like the Nikon EII 8x30 I find I have a hard time taking in the whole field at once. I don't know if it is the way the FOV appears or what. It almost appears like an oblong circle instead of a circle and to me, it is kind of weird. I think I prefer an 8 degree binocular that is better corrected with less distortion at the edges. That way you can examine the FOV more efficiently.
 

[email protected]

Well-known member
Supporter
Then there's the question of facial features that can actually negate the actual use of a super wide FOV. I opened a thread a while ago regarding this issue, where I explained that in my case, probably due to my facial features, I simply can't make use of the FOV of most wide angle binoculars. It's here, some forum members raised very interesting points.
As an example, just today, a few minutes ago I've received a 6.5x32 Levenhuk Sherman Pro. It says 10º FOV but according to Allbinos and other sources it's only 9,1º... and again, I was unable to see the field stop in a "natural and comfortable" viewing position, even if I pulled the eyecups all the way down (I don't wear glasses). I get the same thing when AFOV starts to go beyond 60º and approaches 65º and beyond. I can't see the entire FOV in a EII 8x30 or most other WA I've tried. So in my case, a superwide FOV is less and less important. Eyecups with many intermediate positions are a plus, and finding the perfect fit/match with a particular device is the optical nirvana ;) Something between 60 and 65º does it for me.
I wonder why facial features would affect taking the whole FOV. I think a super large FOV like the NL starts get finicky for eye placement which could be part of the problem.
 

glock24

Member
United States
Anyone know the practical FoV of a pair of human eyeballs?

IMO, this should also be the practical limit of any magnified lens system. If the porn industry has taught us anything; total immersion is where it's at.
 

wllmspd

Well-known member
About 75degree AFOV seems about a good place to aim for. Sometimes you think you can see the field stops, but it is actually because your eye is not in the right place. Certainly there is room for the Alpha boys to widen things a bit more.

Peter
 

PYRTLE

Old Berkshire Boy
Dennis,

I tend to agree with you on this aspect ( unusual I know! ) in that with the 8 x 42 NL, the field of view when I tested one, to me was slightly too wide and niggled me.......something that I thought would never cross my mind having enjoyed the FOV of the 1st generation of EL x 8.5, then subsequently both the FL 8 x 32 and SF 8 x 42 which I still own. This I put down to the fact that both the afore mentioned Zeiss have noticeable excellent "sweet spots" as well as falling off towards the edges - does that make sense ? Consequently the edge to edge sharpness in the x 8 NL made my viewing image "busy". The primary use of all those binos is birding / wildlife.

Surprisingly, nowadays I prefer and use a Zeiss 7 x 42 T*P Dialyt for night sky general stargazing rather than the other two. Some of this I know is sadly down to my failing old tired eyes.

In conclusion, any extra FOV is lost on me nowadays.

Regards.
 

willisoften

Well-known member
United Kingdom
Anyone know the practical FoV of a pair of human eyeballs?

The FOV for the average person is huge compared to binoculars. You can actually detect movement about 5 degrees behind you on each side.
As far as I remember your vision is best about 35 to 40 degrees each side of your nose.
Looking straight ahead:
Your cone of vision is actually flat too. You see better and wider horizontally than vertically. Further you see wider angle of view down than up.

A big thank you to Mrs Van Dyer my biology teacher. I would like to qualify the above statements by saying I failed Biology :)

@denco

As for binoculars with a really wide field of view.
Depends on situation surely? At 20 or 30mtrs looking for small birds across a river for example, a really wide FOV is still only a few meters.
But if you can't even detect movement at the edge of the field. Then I suspect you are correct there is a practical limit.
 

[email protected]

Well-known member
Supporter
The FOV for the average person is huge compared to binoculars. You can actually detect movement about 5 degrees behind you on each side.
As far as I remember your vision is best about 35 to 40 degrees each side of your nose.
Looking straight ahead:
Your cone of vision is actually flat too. You see better and wider horizontally than vertically. Further you see wider angle of view down than up.

A big thank you to Mrs Van Dyer my biology teacher. I would like to qualify the above statements by saying I failed Biology :)

@denco

As for binoculars with a really wide field of view.
Depends on situation surely? At 20 or 30mtrs looking for small birds across a river for example, a really wide FOV is still only a few meters.
But if you can't even detect movement at the edge of the field. Then I suspect you are correct there is a practical limit.
Does that depend on the size of your nose?
 

[email protected]

Well-known member
Supporter
The FOV for the average person is huge compared to binoculars. You can actually detect movement about 5 degrees behind you on each side.
As far as I remember your vision is best about 35 to 40 degrees each side of your nose.
Looking straight ahead:
Your cone of vision is actually flat too. You see better and wider horizontally than vertically. Further you see wider angle of view down than up.

A big thank you to Mrs Van Dyer my biology teacher. I would like to qualify the above statements by saying I failed Biology :)

@denco

As for binoculars with a really wide field of view.
Depends on situation surely? At 20 or 30mtrs looking for small birds across a river for example, a really wide FOV is still only a few meters.
But if you can't even detect movement at the edge of the field. Then I suspect you are correct there is a practical limit.
I agree with that. Sometimes I think my wife has eyes in the back of her head.
 

[email protected]

Well-known member
Supporter
Dennis,

I tend to agree with you on this aspect ( unusual I know! ) in that with the 8 x 42 NL, the field of view when I tested one, to me was slightly too wide and niggled me.......something that I thought would never cross my mind having enjoyed the FOV of the 1st generation of EL x 8.5, then subsequently both the FL 8 x 32 and SF 8 x 42 which I still own. This I put down to the fact that both the afore mentioned Zeiss have noticeable excellent "sweet spots" as well as falling off towards the edges - does that make sense ? Consequently the edge to edge sharpness in the x 8 NL made my viewing image "busy". The primary use of all those binos is birding / wildlife.

Surprisingly, nowadays I prefer and use a Zeiss 7 x 42 T*P Dialyt for night sky general stargazing rather than the other two. Some of this I know is sadly down to my failing old tired eyes.

In conclusion, any extra FOV is lost on me nowadays.

Regards.
I agree on the NL. It was almost too much information for my simple slow processing brain to take in at one time. It was like watching IMAX. I had to look around the FOV to find the birds. I am back to a 8x42 SLC.
 

[email protected]

Well-known member
Supporter
Anyone know the practical FoV of a pair of human eyeballs?

IMO, this should also be the practical limit of any magnified lens system. If the porn industry has taught us anything; total immersion is where it's at.
That makes me wonder if they could develop a Virtual Reality binocular. That would be truly 3-D!
 

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