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3D in roof prism binoculars (1 Viewer)

.The Cooke movie lenses won a Hollywood Oscar, possibly last year or the year before.
They have been Hollywood's lenses of choice for almost 100 years now I think.
Still made in Britain.
 
My glacial internet connection won't allow me to view the video, but from the comments and the blog link it appears that the subject is distortion rather than field curvature, with the author expressing his preference for lenses with distortion (presumably pincushion). Is that right?
 
I watched the video.

The Cooke has a mild fisheye effect (pincushion), and this is very aesthetically pleasing
in the examples presented. It does cause an induced 3D effect, but mainly in terms of
"center is closer to you than sides". It also cause you to focus your attention on
center field, which is why the model looks even prettier. That's really the gist of it
for me: the way your attention is directed, the way your target is 'featured'.
The director mentions he knows the boca is messed up, but the center person is
especially appealing (the woman and the man examples. The background rolls
away from them.

So...yeah, I think it is distortion, but many people would find it quite appealing,
and it enhances "3D" in a way that brings the center target towards you.

I have really gotten into the flat/high-precision view, in the Featherweight family
and the Toei Kogaku 70-degree-apparent models. However, if you want a good
demonstration of the warmth and appeal of a mild pincushion (that does not
accelerate much at the edges!), the Bushnell Customs are the ultimate expression
of that. A quick sweep shows you definite pincushion, but it's almost all in focus
and there is an extra warmth and closeness in your center "feature".
As they say sometimes in scope promotions, it has "pleasant views".

The "sheetmetal" comment is funny. Their set wall is un-naturally flat..
no dimples or seams like in real walls, and the Leica is merciless....but I say: true.
The Cooke makes un-natural walls look more natural...aha.

I like flat a lot, because you can easily see planes of depth through the forest.
It tells you 'where' more accurately. It doesn't love your featured star
like a mild parabolic curvature does, though.

I would enjoy Cooke-filmed shots with people more, but out scouting,
I would learn more about the habitat with a flat view.

This has echoes of stereo hi-fi back in the day.
When Technics came out with super-low distortion, people complained..
...is was dry and analytical. I couldn't stand it either. It got worse
when it came to speakers, and actually killed some harmonics.
Julian Hirsch, famous tester of hi-fi, said something like: "all speakers, like all instruments,
have distortion. The question is, which have distortions that you find pleasing?"
 
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In cameras, I associate fisheye with the "bulging nose" towards you.
Seems like that is just a more severe version of pincusshion, where the sides
fall away quickly (in size).

It is mild, but there is angular distortion, and that's what the guy likes.
The straight walls he calls "sheet metal" under the Leica view are slighty
curved in their lines under Cooke. He likes that. His walls are probably
'stretched canvas' and that's why he sees "sheet metal".
You cannot do that without a little angular distortion.
You don't notice it when holding still, but on a fast pan, Customs definitely show
some rolling ball.

Some like it, if it's subtle and they aren't searching much.
I suspect they like to study a given bird or critter where it lands a lot...
 
Hi Henry,

I've attached a screen shot from an early part of the video to give you some idea of what it's about. The scene from a 21mm Leica lens is shown on the left and an older 21mm Cooke lens on the right. The narrator discusses the difference in terms of visible distortions, and whether or not modern lens corrections are beneficial in so far a three dimensional realism is concerned. To me the effect is quite striking, and corresponds with what I've been thinking about the shortcoming of flat-field lenses. In motion, the 3D effect is even more evident.

There is no discussion of the optical differences between the two lenses, and so any number of design factors could be producing the effect, but I believe the Leica uses a flattener to correct field curvature. It also looks like rectilinear distortion is highly corrected. If that's the case, then it's hard to separate the two influences.

As Tobias pointed out, and perhaps should be emphasized, the visual cues are all 2D, so the 3D perceptual effect is independent of stereopsis.

Ed
 

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I slapped a ruler up...
the Leica field produces straighter lines.
for the walls, there is a receding perspective curve, but not
as much as with the Cooke.
It doesn't necessarily need a flattener, if it has enough length.
Actually, all zooms must necessarily correct curvature.

I think the difference is more dramatic because the movie set
has too many perfectly straight lines. Thing is, when it's small,
the curvature doesn't do anything locally...it just arranges things
over the span of the field.

Here's something to ponder: your eyeball is quite small and curved.
Bigger optics .... film cameras, binoculars, etc...aren't.
Trouble is: they are acting as a proxy for your eye.
Let's look past the flattener as good or evil to the result: a flattened field.
The question is: does a truly flat image match what your eye would see?
Large TV screens are specifically curved to correct for the problem of a flat
image at a fixed distance. You see a virtual image through eyepieces.
Perhaps a slightly curved image is what your eye wants.
It would be interesting to film with Cooke and Leica and look at the results
on a big flat and big curved screen!

In the days of slide projectors, fancier apochromats had a little curve
at screen edges. Was that for a 'natural' look?

I may be stirring more sediment than I'm settling, but
I thnk this is interesting. I think Custom-lovers can do some experiments,
to confirm "hey, when I sweep fast there is a bit of rolling ball, but I sure
love the view when it settles".
 
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I can't say I watched the video more than once, and not with a highly critical eye. But the eye of this photographer (most certainly not a cinematographer and not someone much familiar with binoculars and other non-photographic optics) the differences looked to me like the Leica was aiming to eliminate geometrical distortion and provide a flat plane of focus while the Cooke lens was more like a 'traditional' photographic medium-wide angle lens, having a small amount of barrel distortion and some curvature in it's 'plane' of focus. Similar to the difference between my UC Hexanon 35mm/f2 compared to my M-Hexanon 35mm/f2 (and even more so when compared to modern Leica aspherical 35mm designs). The latter is more 'correct' while the first is more 'traditional' and, to some, more pleasing to the eye when photographing people rather than landscapes or buildings.

But that's just me and I probably missed some things.

...Mike
 
My Porro-Like Roof?

Anyone have any thoughts as to why several people seem to see more 3D with the 10X50 SV than the other SV models ?

EL 10x50 SV distortion characteristics, the wide and sharp edge-to-edge FOV, the deep in-focus DOF, 50mm objectives, My Eyes...who really knows (maybe all the above and more)? ;)

For what ever reason(s), I immediately found the 10x50 spacial view very immersive, with detailed visual clues that create a scene for me, that is a natural and exhilarating 3D as-if-you-are-there experience! I didn't really see or experience this effect in any of the other Swaro, Zeiss or Leica roofs I glassed with over the past 8 months!! :cool:

How do You see the 10x50's Robert?

Ted
 
Hi Ted

I hope to spend more time with them soon when my work allows. There is an opening up, decompressing, easing, of the view that decreases the fatigue factor a significant amount. I may have seen roughly the same thing with the 10X42 SV, it just seemed like I had to mentally work harder to decipher what I saw. I find the difference hard to articulate, but when I made a direct comparison between the two, I immediately knew I would be making the switch. I will try to get a feel for the 3D aspect of the 10X50 when I use them more, but I can say that for me anyway, I found the EL 10X42 SV to have far more pop and WOW factor than the Nikon 10X42 SE when I directly compared them, if not maybe the same 3D effect.



EL 10x50 SV distortion characteristics, the wide and sharp edge-to-edge FOV, the deep in-focus DOF, 50mm objectives, My Eyes...who really knows (maybe all the above and more)? ;)

For what ever reason(s), I immediately found the 10x50 spacial view very immersive, with detailed visual clues that create a scene for me, that is a natural and exhilarating 3D as-if-you-are-there experience! I didn't really see or experience this effect in any of the other Swaro, Zeiss or Leica roofs I glassed with over the past 8 months!! :cool:

How do You see the 10x50's Robert?

Ted
 
I find this subject interesting, we have a discussion of binoculars, both porro and roof,
but mostly about camera lenses, and the movie camera.

When I am evaluating any binocular, the 3-D thing is way down on the list.
In fact it is not even considered.

There are many other more important things that come first.

Jerry
 
When I am evaluating any binocular, the 3-D thing is way down on the list.
In fact it is not even considered.

There are many other more important things that come first.

Jerry

That's me. Maybe I'm taking it for granted(3D). Maybe it's part of what I'm seeing when I NOTICE exceptional optics.

Maybe I need to get some of the Docter Nobilem porros to "see" what I've been missing. I've thought about it......
 
I didn't say I place great value in 3D, I simply asked about 3D in roof prism binoculars. I was under the impression that they didn't have that built in trait like a Porro, but recent comments about the HT made me wonder. If you read the OP, the question is fairly clear. That being said, I don't mind if my threads meander off in interesting directions.:t:
 
Whenever I see the subject of 3-D come up, I usually wonder if the discussion is really about 3-D or depth of focus, or more properly the area of the view that is in focus without moving the wheel. For instance the 10x50 SV EL has quite a large area in focus at anyone time, pretty much from 75 yards or so to infinity. But this is something akin to depth of field or depth of focus and really has little to do with 3-D. The 10x50 SV EL does not have much real 3-D. It has lots of other good stuff to be sure. Like Jerry points out, it is really pretty low on most peoples list of cares.

Anybody who has ever done much with old time aerial photo interpretation where a raised binocular magnifying glass is used over a set of photos and who has seen the way objects on the ground pop up in true 3-D fashion will know what it is. However 3-D, like any other optical feature is either more or less apparent depending on the eyes doing the viewing. I see some stereopsis in any binocular, but don't see the huge amounts a lot of folks assign to a porro binocular.
 
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I found the EL 10X42 SV to have far more pop and WOW factor than the Nikon 10X42 SE when I directly compared them, if not maybe the same 3D effect.

I see some stereopsis in any binocular

I also see stereopsis in all the binos I own or have glassed with, some just present their DOF more naturally and if that is more pleasing to you, then go for it. I did, due to what the EL10x50SV shows me in a complete optical package, but what about this "porro" thing...something different there that my cheap-o pairs attempt to do, but screw up everything else.

Well, have a Habicht 10x40 W GA (Jan 2015 model-used-half of retail) deal coming, gonna See :eek!: what a great classic porro is all about! :t: ;)

Ted
 
My glacial internet connection won't allow me to view the video, but from the comments and the blog link it appears that the subject is distortion rather than field curvature, with the author expressing his preference for lenses with distortion (presumably pincushion). Is that right?

Henry, he sloppily mixes both terms, "flat field" and "distortion". I doubt it is pincushion, especially not in the 21mm lens. It should be barrel or mustache.
 
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