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Old Wednesday 28th June 2017, 08:56   #26
Mike F
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I'm salivating at the prospect of a 7x42 Noctivid.
Rathaus
Rathaus, did you see my response to you in the 3D thread? (post #199)

http://www.birdforum.net/showthread....light=Noctivid

It's a shame if Leica don't produce a 7x42 NTV as I'd snap one up too!
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Old Wednesday 28th June 2017, 12:40   #27
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Rathaus, did you see my response to you in the 3D thread? (post #199)

http://www.birdforum.net/showthread....light=Noctivid

It's a shame if Leica don't produce a 7x42 NTV as I'd snap one up too!
Thanks for the link....but drats! Let's hope they eventually make one. I'd snap up a 7x42 Noctivid sight unseen.

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Old Thursday 29th June 2017, 14:38   #28
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...I'm finding the images through the SV and SF to be akin to viewing an ultra high definition placard or billboard....until I introduce even slight angular motion and all hell breaks loose with the familiar yet bizarre matrix of distortions one must endure in order to witness a compressed and flat stationary image...
More accurate than "one must endure" is "some must endure". I had problems with rolling ball and other more complex gyrations with my Nikon 10x42 LX but I have none with the Swarovski 8.5x42 EL Swarovision, and I'm not alone. A much discussed topic, this. I'm not against binoculars without field flatteners, and I own many, but for some of us who habitually dart our eyes about, the view with flatteners is more natural than without.

--AP
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Old Thursday 29th June 2017, 15:04   #29
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More accurate than "one must endure" is "some must endure". I had problems with rolling ball and other more complex gyrations with my Nikon 10x42 LX but I have none with the Swarovski 8.5x42 EL Swarovision, and I'm not alone. A much discussed topic, this. I'm not against binoculars without field flatteners, and I own many, but for some of us who habitually dart our eyes about, the view with flatteners is more natural than without.

--AP
I've never found the natural world to be 'flat'. This is a bizarre notion to me.
If I wanted to browse outstanding 'flat' high resolution images, all I need do is open one of my bird guide books and dart my eyes about at the detailed pictures on each and every page.
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Old Thursday 29th June 2017, 15:21   #30
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More accurate than "one must endure" is "some must endure". ..................................
......................................... A much discussed topic, this. I'm not against binoculars without field flatteners, and I own many, but for some of us who habitually dart our eyes about, the view with flatteners is more natural than without.

--AP
As a habitual "eye darter" I agree.

We tend to forget that just because the binocular has "flatteners" it does not necessarily have a perfectly flat field. My 8x42 Monarch HG doesn't have quite the sharp edges to its view like my 10x32 EDG, 8x32 LXL and 8x32 SE do but it does have a very wide and expansive view.

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Old Thursday 29th June 2017, 16:03   #31
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I've never found the natural world to be 'flat'. This is a bizarre notion to me.
If I wanted to browse outstanding 'flat' high resolution images, all I need do is open one of my bird guide books and dart my eyes about at the detailed pictures on each and every page.
I don't find the natural world to look flat either. Nor do I find the view through flat field binoculars to be flat. For me, the best flat field designs present a view to my eyes that is well corrected for focus and astigmatism from center to edge. Consequently, when I dart my eyes around in a flat field binocular, I can look on and off axis and have a clear and sharp view, just like when I dart my eyes around when not looking through binoculars. Again, the view doesn't look somehow flat to me, it appears natural but magnified. Other than the difference between stereo and single-eyed vision, and the effect of viewing distance on stereo vision, I don't even understand how a given view can look more flat or dimensional. Maybe that's why I get absolutely no benefit of heightened "realism" from 3-D movies. The view through a binocular (any binocular) does look different than with the naked eye in the sense that distances appear compressed due to the fact that perspective based on the true FOV is not the same as what would obtain with the naked eye equivalent of the apparent FOV, but that is an effect that I am well accustomed to from doing photography using long lenses. In use, I generally don't notice other distortions (pincushion, barrel, differences in magnification center to edge) imposed by binoculars, presumably because my brain adjusts so quickly they don't trigger awareness.

When looking through a binocular without a flat field, darting my eyes off axis yields an unsharp view (esp. if off axis is astigmatic and thus can't be fixed with my eye's ability to correct focus), which I find very unnatural and irritating. Keeping my eyes trained down the center axis of a bin is very also irritating and unnatural for me. Obviously, for some (perhaps even most) people, keeping the eyes relatively fixed straight ahead is not as bothersome as it is for me. As evidence of that, note how popular small eyeglasses lenses (which enforce a rather rigid eye position) have become over the past couple decades in the USA. I can't stand such glasses and prefer an aviator type design that is large enough and that fits close enough for me to move my eyes freely and obtain a sharp view almost to the limits of their range of motion.

--AP
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Old Thursday 29th June 2017, 17:15   #32
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I've never found the natural world to be 'flat'. This is a bizarre notion to me.
If I wanted to browse outstanding 'flat' high resolution images, all I need do is open one of my bird guide books and dart my eyes about at the detailed pictures on each and every page.
No it is not 'flat' Ratty, but neither is it curved in the way that the image through most bins is curved, and posts at the edge of the field of view might look bent through some binos but they aren't in real life either.

So-called flat fields are rarely totally flat and are just another kind of manipulation in the search for an image that is acceptable to more people.

Lee
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Old Friday 30th June 2017, 00:47   #33
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No it is not 'flat' Ratty, but neither is it curved in the way that the image through most bins is curved, and posts at the edge of the field of view might look bent through some binos but they aren't in real life either.

So-called flat fields are rarely totally flat and are just another kind of manipulation in the search for an image that is acceptable to more people.

Lee
Yes, the 'flat field' nomenclature appears to be something of a spectrum...I've seen this nomenclature etched across eyepieces (Nikon HG) or enshrined into a name (FMTX) both of which have nothing approaching the flat field offered up by the SV.

However, the discussion in this thread (as outlined by its title) pertains specifically to the Noctivid, so this is the binocular I am ultimately referencing when talking flat fields. I've owned the SV for about seven years so I know it well...it is a technical marvel.
I stand by my observations so far - when it comes to the natural rendition of a field of view, the Noctivid offers up a far far better balance of compromises than the SV. These are just my observations. I believe the Noctivid will easily accomodate those who enjoy darting their eyes about. I think most people do. It's difficult not to. For reference, I enjoy darting my eyes about, but not from one periphery of the Fov to the other periphery ...I would be nauseated, in the same way I don't try to look at my own eyebrows. The SV will accomodate this practice somewhat better than the Noctivid or any other binocular I know of.

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Old Friday 30th June 2017, 01:15   #34
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Yes, the 'flat field' nomenclature appears to be something of a spectrum...I've seen this nomenclature etched across eyepieces (Nikon HG) or enshrined into a name (FMTX) both of which have nothing approaching the flat field offered up by the SV.

However, the discussion in this thread (as outlined by its title) pertains specifically to the Noctivid, so this is the binocular I am ultimately referencing when talking flat fields. I've owned the SV for about seven years so I know it well...it is a technical marvel.
I stand by my observations so far - when it comes to the natural rendition of a field of view, the Noctivid offers up a far far better balance of compromises than the SV. These are just my observations. I believe the Noctivid will easily accomodate those who enjoy darting their eyes about. I think most people do. It's difficult not to. For reference, I enjoy darting my eyes about, but not from one periphery of the Fov to the other periphery ...I would be nauseated, in the same way I don't try to look at my own eyebrows. The SV will accomodate this practice somewhat better than the Noctivid or any other binocular I know of.

Rathaus
I've enjoyed your post of the situation, and so I assume you like the
flat field view of your Swarovision. Otherwise why would you like and
own it.

You mention being nauseated, not sure about that unless you have had
a bad day with the Noctovid.

Flat field optics are very nice and seem to be at the top of the optical
chain for many users who want the very best.

Nikon, Swarovski and Zeiss feel that way, and I agree.

Sorry this was a Leica thread.

Jerry
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Old Friday 30th June 2017, 11:11   #35
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[quote=Rathaus;3584844

I believe the Noctivid will easily accomodate those who enjoy darting their eyes about.

The SV will accomodate this practice somewhat better than the Noctivid or any other binocular I know of.

Rathaus[/QUOTE]

Ratty

These two statements seem a little at odds with each other and while I don't want to push you into saying which is best at eye-darting, you do seem to be saying Noctivid isn't as good at it as SV. Can you say why?

Lee
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Old Saturday 1st July 2017, 02:47   #36
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Ratty

These two statements seem a little at odds with each other and while I don't want to push you into saying which is best at eye-darting, you do seem to be saying Noctivid isn't as good at it as SV. Can you say why?

Lee
Troubadoris, and other eye swivellers/darters,

The Noctivid is just fine for eye darting. No problems. Better than expected. However, if you wish to swivel your eyes like a gazelle on the Serengeti on the lookout for predators - from one extreme edge of the FOV to the other extreme, I would say the SV is the better choice. I just tried this swivelling now with both binoculars and it really is an extreme form of eye swivelling for myself...nothing I ever do. Others may well enjoy this form of eye swivelling. If you engage in this level of eye swivelling then the SV will be your pick. Also, if you enjoy splitting doubles on the absolute extreme edge of the FOV the SV will be your choice. The Canon 10x is the only bino I have which is at least equal to the SV in this regard.

So, to summarise, I would say for my use, both the SV and the Noctivid accomodate eye darting just fine. To me, however, the Noctivid image appears to be more natural and less manipulated yet will also accomodate all levels of eye darting for myself. An outstanding achievement. If I really swivel my eyeballs out to the last 5deg edge of the FOV, the SV is technically superior to the Noctivid. We are lucky to have such a choice, and most of it will be based on personal taste and image aesthetic preference. I do feel that the Noctivid throws up the finest 'image aesthetic' I've ever seen in a roof binocular.

As usual, the advice is to try them for yourself if possible to check for suitability. I do realise that trying various binoculars can be difficult at times, so we all look to these forums to get some ideas or possibly fill in the gaps.

Cheers,

Rathaus
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Old Saturday 1st July 2017, 08:21   #37
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Troubadoris, and other eye swivellers/darters,

The Noctivid is just fine for eye darting. No problems. Better than expected. However, if you wish to swivel your eyes like a gazelle on the Serengeti on the lookout for predators - from one extreme edge of the FOV to the other extreme, I would say the SV is the better choice. I just tried this swivelling now with both binoculars and it really is an extreme form of eye swivelling for myself...nothing I ever do. Others may well enjoy this form of eye swivelling. If you engage in this level of eye swivelling then the SV will be your pick. Also, if you enjoy splitting doubles on the absolute extreme edge of the FOV the SV will be your choice. The Canon 10x is the only bino I have which is at least equal to the SV in this regard.

So, to summarise, I would say for my use, both the SV and the Noctivid accomodate eye darting just fine. To me, however, the Noctivid image appears to be more natural and less manipulated yet will also accomodate all levels of eye darting for myself. An outstanding achievement. If I really swivel my eyeballs out to the last 5deg edge of the FOV, the SV is technically superior to the Noctivid. We are lucky to have such a choice, and most of it will be based on personal taste and image aesthetic preference. I do feel that the Noctivid throws up the finest 'image aesthetic' I've ever seen in a roof binocular.

As usual, the advice is to try them for yourself if possible to check for suitability. I do realise that trying various binoculars can be difficult at times, so we all look to these forums to get some ideas or possibly fill in the gaps.

Cheers,

Rathaus
Rathaus

OK all is now clear thank you.

And one more thing: may I apologise for presuming to call you 'Ratty' without your permission. It has been pointed out to me that to some folks this could sound derogatory and that was not my intention in any way. On the contrary it was meant as a friendly and informal contraction of Rathaus, such as one friend might use to another. So please accept my apologies if you found this uncomfortable or offensive.

Lee
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Old Saturday 1st July 2017, 08:36   #38
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I must try this "eye darting" thing as I feel I've been missing out for the last 40 years.

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Old Saturday 1st July 2017, 14:43   #39
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I agree with Alexis' post #31. The natural collimated light that falls on the eye exhibits neither field curvature nor astigmatism. Why would removing those aberrations from the collimated light that falls on the eye from the binocular eyepiece cause the image to appear unnatural? I don't think anyone would object to those corrections by themselves.

As I've said elsewhere, I think the objections to the "naturalness" of the field in the SV and others are actually objections to a relative lack of pincushion distortion and the resulting large angular magnification distortion toward the edge of the field, something quite unrelated to correcting field curvature and astigmatim.

As for eye darting, we all do it. Otherwise our heads would be in a state of constant jerking and twitching as we make small angular changes in our central gaze. I recall a few years ago Elkcub provided a link to a paper which found that the eyeballs can comfortably swivel over a range of about 35 before head movement is required. That's more than half the AFOV of the binoculars under discussion. Swiveling the eyeballs over 20 or 25 when reading or looking through a binocular probably goes quite unnoticed, which must explain why people can imagine that their eyes never dart around the field at all. My experience with the field correction of the Zeiss 8x42 FL (and the essentially identical HT) is that the "sweet spot" is just barely adequate over 20 of apparent field. I find better correction of field curvature and astigmatism than that to be a noticeable improvement with no down side.

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Old Saturday 1st July 2017, 14:49   #40
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Rathaus

OK all is now clear thank you.

And one more thing: may I apologise for presuming to call you 'Ratty' without your permission. It has been pointed out to me that to some folks this could sound derogatory and that was not my intention in any way. On the contrary it was meant as a friendly and informal contraction of Rathaus, such as one friend might use to another. So please accept my apologies if you found this uncomfortable or offensive.

Lee
Lee,

Your instincts serve you well. 'Ratty' (or most anything else) is absolutely fine by me

Rathaus

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Old Saturday 1st July 2017, 16:12   #41
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As for eye darting, we all do it. Otherwise our heads would be in a state of constant jerking and twitching as we make small angular changes in our central gaze. I recall a few years ago Elkcub provided a link to a paper which found that the eyeballs can comfortably swivel over a range of about 35 before head movement is required. That's more than half the AFOV of the binoculars under discussion. Swiveling the eyeballs over 20 or 25 when reading or looking through a binocular probably goes quite unnoticed, which must explain why people can imagine that their eyes never dart around the field at all.
Henry
A large proportion of the discussions we have on the Forum about 'eye-darting' is usually in the context of the sharpness (or otherwise) of the edge of the field of view of a particular model of binos. Often there is mention of exploring the field of view from edge to edge and it is this 'extreme eye-darting' that I personally find uncomfortable.

You are absolutely right that a good deal of eye-wandering takes place within a pretty wide segment of the field of view but for me this is an entirely different thing from darting from field edge to field edge.

Other folks are apparently quite comfortable doing this.

Lee
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Old Saturday 1st July 2017, 16:13   #42
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Lee,

Your instincts serve you well. 'Ratty' (or most anything else) is absolutely fine by me

Rathaus
Thanks Rathaus

Lee
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Old Saturday 1st July 2017, 20:46   #43
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Chuck, what about the comparison of the image, between them, other than for the magnification? Not all of us get this chance! Thanks.
The image is very similar...BUT more times than not I thought the Noctivid WAS the brighter of the two. It's pretty plain the Noctivid is Leica's cream of their crop. Just how MUCH better than the Ultravid HD+...hard to determine without identical magnifications. My guess is not a WHOLE lot of difference other than the obvious.
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Old Sunday 2nd July 2017, 15:30   #44
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A large proportion of the discussions we have on the Forum about 'eye-darting' is usually in the context of the sharpness (or otherwise) of the edge of the field of view of a particular model of binos. Often there is mention of exploring the field of view from edge to edge and it is this 'extreme eye-darting' that I personally find uncomfortable.

You are absolutely right that a good deal of eye-wandering takes place within a pretty wide segment of the field of view but for me this is an entirely different thing from darting from field edge to field edge.

Other folks are apparently quite comfortable doing this.

Lee
What I don't understand is the idea that complete correction of off-axis astigmatism and field curvature creates an unnaturally "flat" view. That's why I've offered confusion between the meanings of field curvature and the unrelated characteristics of distortion as the probable source of such complaints. Your post #32 seems to be an example.

"No it (the real world) is not 'flat' Ratty, but neither is it curved in the way that the image through most bins is curved, and posts at the edge of the field of view might look bent through some binos but they aren't in real life either.

So-called flat fields are rarely totally flat and are just another kind of manipulation in the search for an image that is acceptable to more people."

Bent posts at the edge of the field of view result from distortion, not field curvature.

Henry
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Old Sunday 2nd July 2017, 16:11   #45
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What I don't understand is the idea that complete correction of off-axis astigmatism and field curvature creates an unnaturally "flat" view. That's why I've offered confusion between the meanings of field curvature and the unrelated characteristics of distortion as the probable source of such complaints. Your post #32 seems to be an example.

"No it (the real world) is not 'flat' Ratty, but neither is it curved in the way that the image through most bins is curved, and posts at the edge of the field of view might look bent through some binos but they aren't in real life either.

So-called flat fields are rarely totally flat and are just another kind of manipulation in the search for an image that is acceptable to more people."

Bent posts at the edge of the field of view result from distortion, not field curvature.

Henry
Yes Henry, I understand the difference between field curvature and distortion and what I was seeking to convey to Rathaus was that the view through binos isn't 'natural' whether field-flattened or not.

Lee
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Old Sunday 2nd July 2017, 16:26   #46
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I agree that the view through binoculars is not natural at all.
For a start one does not have a horizontal view of perhaps 160 degrees.

In fact I think the view through my distance glasses is not natural either, as I cannot view a very wide panorama without the frame intruding and the view outside the frame being unclear. Also the frame edge interferes with the view, cutting off bits.

What I don't like about 'distortionless' or rectilinear eyepieces such as in the Russian 7x30 and 10x42 is the sudden change towards the edge of bad angular magnification changes. Squashed full moons. And weird panning effects.

I like 82 degree Naglers and the odd 90 degree eyepieces I have tried. I don't like a 100 degree Ethos.

Horace Dall built a wide angle stereo camera based on Zeiss lenses that had 70 degree fields, as he thought this gave the best stereo photos. The stereo pairs were indeed very nice and better than most stereo pairs.
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Old Sunday 2nd July 2017, 16:53   #47
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Until I came on this forum I'd never even thought about the way that I look through binoculars. Personally I find that I do move my eyes around the FOV (which as has been said is surely the norm) but I would say not usually beyond the central 60-70%. If, as an exercise, I look to the periphery of the image I am most definitely moving my eyes much more up and down or from side to side than I do when not using bins. In fact I find it quite unnatural and even somewhat uncomfortable to do so. AFAIK I have perfectly normal vision(!) so there's no physical reason why my eye movement would be restricted in any way - I just don't like doing it.

Comparing the UVHD+ and NV with regard to image sharpness at the extremities, I would say that roughly speaking the UVHD+ is sharp in the central 80% and the NV sharp central 90% (in other words to within 10% and 5% of the edge respectively) of the FOV. So for me, in practice, I notice no difference in this respect between them because I simply don't look there. Doing so would be akin to moving my eyes as far left and right or up and down as I can in normal vision without bins, and I never do that.
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Old Sunday 2nd July 2017, 17:12   #48
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Lee,

Only the geometric and angular magnification distortions are "unnatural" and not fully correctable, but they are totally unrelated to field curvature and astigmatism.

There is no loss of "naturalness" in a binocular image that is fully or nearly fully corrected for field curvature (which really also means full correction of astigmatism since both the sagittal and tangential foci must be coincident). That is the way the world presents itself to our eyes without binoculars. The situation is very much the same as correcting chromatic aberration. There is no trade-off or downside to full correction.

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Old Sunday 2nd July 2017, 17:22   #49
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Until I came on this forum I'd never even thought about the way that I look through binoculars. Personally I find that I do move my eyes around the FOV (which as has been said is surely the norm) but I would say not usually beyond the central 60-70%. If, as an exercise, I look to the periphery of the image I am most definitely moving my eyes much more up and down or from side to side than I do when not using bins. In fact I find it quite unnatural and even somewhat uncomfortable to do so. AFAIK I have perfectly normal vision(!) so there's no physical reason why my eye movement would be restricted in any way - I just don't like doing it.

Comparing the UVHD+ and NV with regard to image sharpness at the extremities, I would say that roughly speaking the UVHD+ is sharp in the central 80% and the NV sharp central 90% (in other words to within 10% and 5% of the edge respectively) of the FOV. So for me, in practice, I notice no difference in this respect between them because I simply don't look there. Doing so would be akin to moving my eyes as far left and right or up and down as I can in normal vision without bins, and I never do that.
This is pretty much my experience too. Nicely put.

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Old Sunday 2nd July 2017, 17:32   #50
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Lee,

Only the geometric and angular magnification distortions are "unnatural" and not fully correctable, but they are totally unrelated to field curvature and astigmatism.

There is no loss of "naturalness" in a binocular image that is fully or nearly fully corrected for field curvature (which really also means full correction of astigmatism since both the sagittal and tangential foci must be coincident). That is the way the world presents itself to our eyes without binoculars. The situation is very much the same as correcting chromatic aberration. There is no trade-off or downside to full correction.

Henry
Here is what Rathaus posted a propos field-flattened binos:
"I've never found the natural world to be 'flat'. This is a bizarre notion to me".
The corollary of this seemed to be the notion that binos without field flatteners provide a wholly natural view and my post meant to challenge that.
Did I choose the wrong examples Henry?

Lee

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