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Why can' they make an alpha binocular with a 600 foot FOV and sharp edges? (4 Viewers)

I assume that you can roll your eyes side to side and see it. I do that routinely with modern "wide" field binoculars but can also seethe edges through the corners of my eyes.

Bob

I posted this above but I will try again. With that kind of field, if you try and look directly at the edge, say to the left, you will get blackout with your right eye. If you force the issue when you get there, you will see two edges
 
I posted this above but I will try again. With that kind of field, if you try and look directly at the edge, say to the left, you will get blackout with your right eye. If you force the issue when you get there, you will see two edges

I understand what Steve is referring to but want to offer some clarification. I think this is going to depend on the model of EWA we are referring to as well as our individual facial dimensions. I have run into Steve's issue with several models. Others I don't have that issue. I can easily roll my eyes around the entire view and see the field stop quite clearly....and I don't get blackouts in either eye. For me it depends on the ocular design and how far it is recessed from the edge of the "eyecup". I put eyecup in quotes simply because, in somce cases, there isn't an eyecup as I have removed it. Not sure what I want to call the eyepiece "column"...the metal tube that the eocular lens actually is mounted into.

It is also going to vary based on the listed field of view. We are throwing around the term "extra wide angle" or "super wide angle" pretty loosely. I guess for the sake of discussion, and assuming a 7x35 model, that anything with 10 degrees or wider would be a safe bet. That would rule out the Nikon WF/Gold Sentinels and a few others. With many 10 and 10.5 degree models I don't have problems seeing the field stops. With some 11 degree models I can see the field stops clearly but others I cannot. Once you get above that then it is difficult to see the edges...at least for what I have on hand and for my facial dimensions.
 
I understand what Steve is referring to but want to offer some clarification. I think this is going to depend on the model of EWA we are referring to as well as our individual facial dimensions. I have run into Steve's issue with several models. Others I don't have that issue. I can easily roll my eyes around the entire view and see the field stop quite clearly....and I don't get blackouts in either eye. For me it depends on the ocular design and how far it is recessed from the edge of the "eyecup". I put eyecup in quotes simply because, in somce cases, there isn't an eyecup as I have removed it. Not sure what I want to call the eyepiece "column"...the metal tube that the eocular lens actually is mounted into.

It is also going to vary based on the listed field of view. We are throwing around the term "extra wide angle" or "super wide angle" pretty loosely. I guess for the sake of discussion, and assuming a 7x35 model, that anything with 10 degrees or wider would be a safe bet. That would rule out the Nikon WF/Gold Sentinels and a few others. With many 10 and 10.5 degree models I don't have problems seeing the field stops. With some 11 degree models I can see the field stops clearly but others I cannot. Once you get above that then it is difficult to see the edges...at least for what I have on hand and for my facial dimensions.

So you don't see any edge so it is like your eye with normal vision. You are not limited by a place where the field just stops it just goes off into infinity. Interesting.
 
It is also going to vary based on the listed field of view. We are throwing around the term "extra wide angle" or "super wide angle" pretty loosely. I guess for the sake of discussion, and assuming a 7x35 model, that anything with 10 degrees or wider would be a safe bet. That would rule out the Nikon WF/Gold Sentinels and a few others. With many 10 and 10.5 degree models I don't have problems seeing the field stops. With some 11 degree models I can see the field stops clearly but others I cannot. Once you get above that then it is difficult to see the edges...at least for what I have on hand and for my facial dimensions.

That is where it is for me too. If you want to see how your particular eyes will react to the presence of the extra wide field edge effect, than I think you need 11* @ 7x. I have a Swift Nighthawk 8x40 @ 9.5* which shows the same thing. Those afov's are 76 and 77*. I have a Sans & Streriffe Viking 8x30 @ 10* (80*) but it is not so illustrative of this fov effect. It has a little eye relief and I get best views about 3-4 mm off the ocular. Be aware if you are looking for something to stick to that level I think. Wide angle or extra wide angle was applied for 9.5* clear out to 13*.

I really get the feeling sometimes that some people are bound and determined to be bothered by the edge effect. Maybe some of them will see the edge at 100* afov. Maybe they can see their left ear with their right eye too. ;) And again, the edge does not disappear, it moves out into (more or less) the periphery of the view, where its presence is lessened a great deal, but not removed.

I'm going to address Henry's comments on actual vs stated fov too. Just need to set up and take some notes. It is kind of embarrassing I have not done that already.

The less eye relief the greater the wide angle effect is. Like Frank, on all of the best binoculars to illustrate this I too, gave removed the eye cup. Some of the blackout may well be physical contact of the eye lid and the ocular lens. But IF you back off, the view shrinks.

Dennis,

Yes the effect is a lot (not completely) like having your normal vision magnified edge to edge, in the sense of a lesened awareness of the presence of the edge of the field.
 
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Yes the effect is a lot (not completely) like having your normal vision magnified edge to edge, in the sense of a lesened awareness of the presence of the edge of the field.

It seems as though the use of glasses pretty much precludes this perception of magnified normal vision.
Certainly extra wide angle binoculars have never worked for me, perhaps because my needing to correct 300/400 vision ensures that there is never enough eye relief.
That said, the old Zeiss 7x42 did give me more of a 'picture window' effect than any other glass I've ever owned. It would be wonderful to get it in a higher power glass.
 
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That said, the old Zeiss 7x42 did give me more of a 'picture window' effect than any other glass I've ever owned. It would be wonderful to get it in a higher power glass.

I think I know what you're talking about. Take a look at: http://www.birdforum.net/showthread.php?p=2326669#post2326669

So far as I'm concerned the new 8x42 SLC HD meets the requirement splendidly with an 18.5mm eye relief. I've put aside my 7x42 BGATP with its picture window for the duration. Unfortunately, Cameraland seems to be out of their salesman's samples, but the binoculars are available for about $1900. Expensive, yes. Worth it, ... YES!

The SVs are another way to go.

Ed
 
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Back to the topic of why the need for an EWF birding bin, which Frank touched upon in post #51. Here are some specific examples.

I have a suet feeder in my backyard, and it gets very popular in the winter - sparrows, woodpeckers, nuthatches, chickadees, Blue Jays, and even the occasional squirrel all vying for position to get at the peanut butter flavored fatty concoction.

Once while I was sitting in the backyard on a cool but not cold winter's day, I caught this interaction btwn sparrows and a nuthatch.

Three sparrows were vying for a position on the suet feeder, with one waiting on a nearby branch and two on the feeder. Here comes a nuthatch creeping down the trunk of the tree. Seeing the sparrows, he spreads his wings and flaps them, as if it to say, get lost, it's my turn. They ignored him, so he came closer and did the same display and also made some noise. The most aggressive sparrow on the feeder made some nose too and did a threatening lunge at the nuthatch to get in the last word, but then three sparrows scattered and the nuthatch gained control of the suet.

With the 8.8* FOV 8x30 EII, I could watch the nuthatch and the sparrows reaction including the sparrow on the branch all in one view. With the 6.5* Swift 8x44 ED, I had to keep going back and forth from nuthatch to suet feeder to sparrow on the branch to see the whole thing unfold.

Another example. I walking to the park and had the 8x EII with me. I spotted a hawk circling about a block or two away on the other side of the road.

Starlings and mourning doves by the dozen were perched on power lines in the foreground.

As the hawk came closer he began to dive toward the power lines and both the starlings and morning doves took off.

They began swarming, each species to his own, but as the hawk came closer, the starlings and mourning doves joined up, turned and twisted in formation like Farnborough Air Show acrobatics.

Anyone who has watched flocks of starlings and mourning doves fly, knows their flight pattern is quite different - yet when joined together, they adopted the same pattern.

I thought that was an amazing example of cooperation between species. The hawk who was now visible in the same FOV was perplexed, befuddled, and desperately trying to find a straggler, but no dice. After a couple approaches, which were meet with evasive maneuvers, he gave up and flew away.

I caught the entire action in one FOV w/out having to toggle back and forth between the front and back of the swarm and the hawk. This could never happen with a Monarch or Pentax 8x43 ED and other bins with moderate FsOV.

On another day, I watched a couple flocks of starlings join forces at another location to avoid a hawk. They would fly around and join up and then head for a tree. Stay there for a while until someone gave the signal a
nd they'd swarm again and lit down in another tree. Saw this action in the 9* 7x36 ED2.

So, yes, if you simply want to ID a species, you don't need a EWF or even a WF bin, a Monarch or Pentax 8x43 will do fine. But if you want to study bird interactions and watch birds flying in formation and study flock behavior, having a 9* FOV really helps.

Brock
 
Brock,

The 804ED Audubon has a FOV = 430', which computes to 8.2º. It has an apparent field of 69.75 degree, which is slightly smaller than the 70.4 degrees of the E2. They both round to 70 degrees, and in effect are equally wide. Real fields of 8.8 vs. 8.2 also aren't all that different.

In any event, the property you're describing relates to the real field and could be accomplished with an undistinguished 6x instrument that most people would consider narrow, e.g., 6 x 9º (real) = 54º (apparent).

Ed
 
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Brock,

The 804ED Audubon has a FOV = 430', which computes to 8.2º. It has an apparent field of 69.75 degree, which is slightly smaller than the 70.4 degrees of the E2. They both round to 70 degrees, and in effect are equally wide. Real fields of 8.8 vs. 8.2 also aren't all that different.

In any event, the property you're describing relates to the real field and could be accomplished with an undistinguished 6x instrument that most people would consider narrow, e.g., 6 x 9º (real) = 54º (apparent).

Ed

"Real fields of 8.8 vs. 8.2 also aren't all that different."

I don't know about that! I see a signifigant difference. For each 20' of FOV I see a difference.
 
Back to the topic of why the need for an EWF birding bin, which Frank touched upon in post #51. Here are some specific examples.

I have a suet feeder in my backyard, and it gets very popular in the winter - sparrows, woodpeckers, nuthatches, chickadees, Blue Jays, and even the occasional squirrel all vying for position to get at the peanut butter flavored fatty concoction.

Once while I was sitting in the backyard on a cool but not cold winter's day, I caught this interaction btwn sparrows and a nuthatch.

Three sparrows were vying for a position on the suet feeder, with one waiting on a nearby branch and two on the feeder. Here comes a nuthatch creeping down the trunk of the tree. Seeing the sparrows, he spreads his wings and flaps them, as if it to say, get lost, it's my turn. They ignored him, so he came closer and did the same display and also made some noise. The most aggressive sparrow on the feeder made some nose too and did a threatening lunge at the nuthatch to get in the last word, but then three sparrows scattered and the nuthatch gained control of the suet.

With the 8.8* FOV 8x30 EII, I could watch the nuthatch and the sparrows reaction including the sparrow on the branch all in one view. With the 6.5* Swift 8x44 ED, I had to keep going back and forth from nuthatch to suet feeder to sparrow on the branch to see the whole thing unfold.

Another example. I walking to the park and had the 8x EII with me. I spotted a hawk circling about a block or two away on the other side of the road.

Starlings and mourning doves by the dozen were perched on power lines in the foreground.

As the hawk came closer he began to dive toward the power lines and both the starlings and morning doves took off.

They began swarming, each species to his own, but as the hawk came closer, the starlings and mourning doves joined up, turned and twisted in formation like Farnborough Air Show acrobatics.

Anyone who has watched flocks of starlings and mourning doves fly, knows their flight pattern is quite different - yet when joined together, they adopted the same pattern.

I thought that was an amazing example of cooperation between species. The hawk who was now visible in the same FOV was perplexed, befuddled, and desperately trying to find a straggler, but no dice. After a couple approaches, which were meet with evasive maneuvers, he gave up and flew away.

I caught the entire action in one FOV w/out having to toggle back and forth between the front and back of the swarm and the hawk. This could never happen with a Monarch or Pentax 8x43 ED and other bins with moderate FsOV.

On another day, I watched a couple flocks of starlings join forces at another location to avoid a hawk. They would fly around and join up and then head for a tree. Stay there for a while until someone gave the signal a
nd they'd swarm again and lit down in another tree. Saw this action in the 9* 7x36 ED2.

So, yes, if you simply want to ID a species, you don't need a EWF or even a WF bin, a Monarch or Pentax 8x43 will do fine. But if you want to study bird interactions and watch birds flying in formation and study flock behavior, having a 9* FOV really helps.

Brock

Good point! Brock. Exactly my feelings. So many times you are not looking at just one bird but several interacting and that big FOV of 462 feet is really helpful with that EII. 9 degree FOV and above is really nice. I am going to try the new Vortex Talon 8x32 with the 9 degree FOV @477 feet. That's 15 feet more than the EII. If the edges are pretty sharp it should be quite good. Probably not as good optically as the EII.
 
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Re: Wide FOV

When you have a "huge" field of view with SOFT edges you end up with a lot of off-center blur, constant refocus and/or constant movement to maintain focus. Most, if not all, of the mentioned "wide-field" bins have soft edges!
I used a Leica 7X42 with a 420' real FOV for many years and I never enjoyed its "field of view" as much as my 8X32 SE with a real field of 393'. The Leica was dead sharp in the centerfield, but off-center it suffered from soft edges and it was often a serious distraction.

Swarovski nailed the problem: combine super sharp edges with a 399' FOV and the experience will be totally captivating. They proved there's simply no need for a larger FOV, even in very close quarters.

It's really good you can be happy!

Now what about those who can't because there aren't any extra wide angle alphas? Soft edges or not...
 
It's really good you can be happy!

Now what about those who can't because there aren't any extra wide angle alphas? Soft edges or not...

"Swarovski nailed the problem: combine super sharp edges with a 399' FOV and the experience will be totally captivating. They proved there's simply no need for a larger FOV, even in very close quarters"

You don't think an SV view with a 500 foot FOV would be cool? I do. I don't think you would want to go back to 400 feet.
 
What happened to 600'?

Most of the experts seem to think there is not an eyepiece available for a binocular that would give you a 600' FOV with 8x magnification so I have lowered my dream FOV to something that is within reason and could be accomplished. I'll try the Vortex Talon 8x32 when it comes out but I think the edges are going to be too soft for me. We will see. Does anybody know of a roof prism with a 500' FOV and pretty sharp edges.
 
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Sorry Dennis. Not only doesn't any manufacturer currently make that model but I don't any manufacturer ever has. The parameters would require an extremely complex, and most likely costly, eyepiece. That Swarovision you owned was probably the closest thing to it. The Swarovision 8x32 set to debut is likely to have a larger field of view than the 8.5x42 so it is probably going to be the closest thing to what you are looking for.

It would not work for me though in terms of an ideal binocular because, again, it is only going to have a 4 mm exit pupil.
 
Frank - I was looking at your collection of wide field binos and didn't notice the
Bushnell 7x35 Rangemaster, which arguably is among the best wide field ever produced. Have you not run across this model yet. John
 
John,

No, I have seen it and have actually bid on a couple.

One small issue though...everybody that buys this type of binocular knows about the Rangemaster and they don't sell cheaply. I don't remember what the last one sold for but it was significantly more than what I was willing to spend on a vintage porro.

My thing is more of finding a "diamond in the rough" rather than just getting a known performer. I probably would like to compare one to what I have currently on hand just for peace of mind.
 
John,

No, I have seen it and have actually bid on a couple.

One small issue though...everybody that buys this type of binocular knows about the Rangemaster and they don't sell cheaply. I don't remember what the last one sold for but it was significantly more than what I was willing to spend on a vintage porro.

My thing is more of finding a "diamond in the rough" rather than just getting a known performer. I probably would like to compare one to what I have currently on hand just for peace of mind.

I am going to try the Vortex Talon 8x32 when it becomes available. A 477 foot FOV might be enough for me and it meets my other requirements of weight and ergonomics and it is waterproof. I will probably buy it and try it and if I don't like it I will send it back. I have a feeling the edges will be too soft for me. I will write a review when I get it.
 
John,

No, I have seen it and have actually bid on a couple.

One small issue though...everybody that buys this type of binocular knows about the Rangemaster and they don't sell cheaply. I don't remember what the last one sold for but it was significantly more than what I was willing to spend on a vintage porro.

My thing is more of finding a "diamond in the rough" rather than just getting a known performer. I probably would like to compare one to what I have currently on hand just for peace of mind.

Those Rangemasters usually go for upwards of $200. The deal is "you snooze you loose". Which is just what I did last night. I was looking through new searches and there was what appeared a pristine Rangemaster buy it now. free shipping for $99. I went through the rest of the searches and it was gone when I got back to it. My excuse is it was late and I was tired ;).
 
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