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Narrow vs. wide FOV - "feeling" the difference (1 Viewer)

gkamov

Bulgarian birder
Bulgaria
I was birdwatching the other day with my cheap and cheerful Olympus 7x35 (9.3 FOV) and suddenly felt the difference between binoculars with narrower and wider field of view. I would describe it as follows:
  • With a narrow FOV you "move the bird towards you", i.e. there is a distinct feeling of looking through some kind of optical device, trying to get a certain image closer to you.
  • With a wide FOV, you "move yourself towards the bird", i.e. the feeling is as if you travel dozens of meters forward in space with an almost natural view through your own eyes.
My personal choice is definitely wide FOV. Even though the magnification is smaller (in the case of these particular binoculars, at least), I am somehow able to perceive the bird in context and observe it more... naturally, I would say. It's no surprise to me that Zeiss and Swarovski are putting a lot of effort in creating wider FOV binoculars - although they probably won't have the same 3D effect as a porro prism. But that's another story :)

Any thoughts on this?
 

eitanaltman

Well-known member
What an interesting and accurate way to put it -- "move the bird towards you" vs "move yourself towards the bird". I think that's a very good way of summarizing what I've seen in a lot of discussions about "natural" and "transparent" views, and I think it is about more than just FOV but also magnification and field curvature, both of which impact the sense of "depth" in the image.

In a recent thread I shared an anecdote about how my wife tried my Nikon 10x32 EDG and found them uncomfortable, she described as feeling like the image was smashed up against her face like looking at a microscope slide, whereas her normal Leica 8x32 UVHD felt more "natural" like she was just looking at something closer.

My two primary binoculars currently are that 10x32 EDG and a Leica 7x42 UVHD, and it perfectly describes the relative sensation of using each. The EDG feels like zooming in, like viewing the world through a Nikkor ED prime telephoto lens. Whereas the 7x42 with its glorious wide, deep, transparent view just feels so "natural" as though I'm simply standing closer to the stuff I'm looking at.

Cheers to this! 🍻
 

horukuru

Here I Come !
Hence my favourite binocular is the 8x32 followed by the 10x32 and 10x42 ELs. The wide FOV is addictive and relaxing on my eyes
 

[email protected]

Well-known member
Supporter
I was birdwatching the other day with my cheap and cheerful Olympus 7x35 (9.3 FOV) and suddenly felt the difference between binoculars with narrower and wider field of view. I would describe it as follows:
  • With a narrow FOV you "move the bird towards you", i.e. there is a distinct feeling of looking through some kind of optical device, trying to get a certain image closer to you.
  • With a wide FOV, you "move yourself towards the bird", i.e. the feeling is as if you travel dozens of meters forward in space with an almost natural view through your own eyes.
My personal choice is definitely wide FOV. Even though the magnification is smaller (in the case of these particular binoculars, at least), I am somehow able to perceive the bird in context and observe it more... naturally, I would say. It's no surprise to me that Zeiss and Swarovski are putting a lot of effort in creating wider FOV binoculars - although they probably won't have the same 3D effect as a porro prism. But that's another story :)

Any thoughts on this?
You are expressing it a different way but you are saying the same thing when birders say that a binocular has a more immersive view, or they feel they are drawn into the FOV rather than looking at a bird at the end of a tunnel. That is what is nice about a large FOV but the AFOV or the FOV in degrees multiplied by the magnification is even more important. The higher the AFOV in degrees the more immersive the binocular. You are correct that a roof will never have the 3D view of a porro prism and that gives a porro prism binocular a more realistic view than the flat view of a roof. That is a big advantage of a porro prism. But an exceptional roof prism with its huge FOV and sharp edges like the Swarovski NL is a pretty sweet view nonetheless. Roof prisms have their advantages also.
 
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Had.enough

Registered User
Supporter
It's something I had never appreciated. And when deciding between binoculars at a shop, "unknowingly" chose a binocular with a narrower field of view, because I could make out more details through it.

That's not necessarily a bad criteria to use, to a certain degree.. you always have the chance of seeing something thru a narrower FOV pair..
You will never see that extra detail thru the wider FOV pair.
 

Jessie-66

Germany
We should differentiate between impression and reality, between apparent angle of view and real field of view in binoculars - in conjunction with human eyes, which have experienced a long evolution:
Compared to the field of view, the field of view is about 60 degrees wider on both sides; up and down it is about 40 degrees wider. The ability to describe the visual impression also plays a major role in the practical measurement of visual acuity.
"The size of the eye pupil physically limits the resolution of the eyeball, physiologically it is the density of the receptors (rods and cones) and the signal processing by retinal ganglion cells (see their receptive fields). The resolution reaches its highest value with sufficient brightness in the center of the fovea centralis ("visual fossa"), i.e. with central fixation. The area of highest visual acuity (the "foveal bouquet") comprises only about 8 to 16 angular minutes, i.e. it is much smaller than the foveola, which measures about 1°. From there it is a continuous decrease, approximately in the form of a hyperbola. With an eccentric fixation of about 1° the peripheral visual acuity has already decreased to half of its original value".
(Source: translated german wikipedia)
People perceive details in the central area more detailed than in the peripheral area. Outer areas are important for the detection of movements and thus dangers, but the overall human system primarily wants to process more important informations first.
I therefore prefer wide-angle binoculars. A wide angle of vision is more important to me than edge-to-edge sharpness. My optimization goal is to find "sweet spots", i.e. areas with central sharpness as large as financially possible for me - with maximum real field of view, sharp and/or unsharp. I love edge-to-edge sharpness, but it is less important for the "multi-size optimization" for most informations. Thanks for the interesting problem description. I and my brain want to see so many informations as possible (objective: angle/diameter of sweet spot, real FoV, DoF, magnification, contrasts) - and a nice, impressive image (subjective: appearant FoV, color rendering). Little differences of transmission (> 85 %) from modern, good bins in daylight and twilight observation are imho not so important.
Multi-size optimization for different observation objects is less successful with only one binocular than with several "specialists". A person does not like carrying heavy tools. ;-)
 
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