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Why is it......

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bill47 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bill47 Quote  Post ReplyReply Direct Link To This Post Topic: Why is it......
    Posted: September/01/2005 at 12:49

Why is it that a variable scope is acceptable, but zoom binoculars are not?

 

I have been using fixed power scopes and binoculars for 45+ years.  Zoom binoculars are terrible and I haven't been daring enough to try a variable scope.  Been hunting with the same Weaver K4s during that time with great success in the mountains of southern Arizona, so why risk it?

 

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Stephanie View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Stephanie Quote  Post ReplyReply Direct Link To This Post Posted: September/01/2005 at 12:58

You should take a look at the Leica Duovid 10 +15 x 50 - the binocular-spotting scopes
With its 15 x magnification, the Duovid with 50 mm objective lens bridges the gap between binocular and spotting scope.

LEICA DUOVID 10 +15 x 50
This Duovid is a high performance binocular that, with a flick of the wrist, becomes a binocular-spotting scope. The 10 x magnification allows for shake-free viewing and a larger field of view. By switching to 15 x one achieves a level of detail recognition previously found only in spotting scopes. Due to its high level of optical performance, the 50 mm Duovid is also well suited for astronomy -- it comes delivered with a tripod adapter to provide added stability.
The ergonomic design and the soft-touch rubber armoring in black or green allow for a secure and shake-free handling of the binocular, even while wearing gloves. I don't think you would be disappointed with the Leica brand of binoculars..

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Dale Clifford View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: September/01/2005 at 16:37

The answer no one wants to really read.

Again Parallex rears it's ugly head. If you think parallex causes problems in the shooting world, you should talk to golfers. Should I hold my head directly over the ball or over the club. How do we make two optical images converge to the same mapping in the brain under variable conditions (zoom binoculars)?

Now for the really ugly answer.

Normal space exists in Euclidean norm vector where the metric distances between objects exists in Cartesian co-ordinates. The brain translates this back into a vector in the brain that defines the spatial distance between the objects and the human in terms of distance and magnitude of the vector. This is how it knows where your left hand is in relation to the right hand. The velocity vector is slightly curved in the brain mapping. Thus railroad tracks converge at a distance when their norm vector is still 1(in reality they are not converging and no the moon is not bigger on rising). The steady state condition of the brain mapping extends to two spatial dimensions by making each summation a function of both x and y. (method used by neural net control systems in robots for optical recognition software). The other factor is the mapping from the retina to visual cortex. There is an enormous magnification of the central retinal representation in cortex relative to that of peripheral retina (norm no longer Euclicidian and cartesian). The left (and the most important reason) and right halves of the retinas are each seperately mapped onto the opposite visual cortex. Thus the map of the right half of each retina onto the left visual cortex in humans is distorted where the vertical meridian maps onto the boundary of the cortical representation. The polar co-ordinate representations are mapped into the cortical co-ordinates. (ln(1+R)) and theta (degrees). This mapping transformations takes on highly characteristics ways. If the brain is asymptotically stable (not on drugs) parallel lines will bend. (If on drugs excited and not stable-hallucinations -it was the wheel of Ezekial -man!!) This non-linear effect from the visual to the brain mapping forms stable "attractors". Somewhat like looking at Esher prints- you see it one way one time another way another time.

Having said that I am going dove hunting.

p.s. if you want the math I will send it along

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bill47 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bill47 Quote  Post ReplyReply Direct Link To This Post Posted: September/01/2005 at 16:52

Thanks!  I knew I was overlooking something simple.

 

I'm going dove hunting too.  With the season opening on my birthday, I always celebrate with a bang.

 

Hasta la vista.

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hangfire View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hangfire Quote  Post ReplyReply Direct Link To This Post Posted: September/30/2005 at 21:00
Originally posted by Dale Clifford Dale Clifford wrote:

The answer no one wants to really read.



I agree. Really ugly answer, that no one should bother reading.


Originally posted by Dale Clifford Dale Clifford wrote:


Normal space exists in Euclidean norm vector where the metric distances between objects exists in Cartesian co-ordinates.


A grammatically and semantically meaningless sentence. There is no evidence that mandates that space be measured in either Euclidean or Cartesian norms or coordinates, let alone that space "exists" there.


Originally posted by Dale Clifford Dale Clifford wrote:

The brain translates this back into a vector in the brain that defines the spatial distance between the objects and the human in terms of distance and magnitude of the vector.



Euclid gave us geometry and DeCart gave us coordinates; the brain, analog computer that it is, uses neither to determine distance (unless measuring instruments and electronic calculators are introduced to it).


Originally posted by Dale Clifford Dale Clifford wrote:


This is how it knows where your left hand is in relation to the right hand.


No, if that were true, a blind person would not know the relationship between his/her two hands; as it is, a blind person knows exactly when they are about to touch.


Discarding rest of flawed discussion.

HF

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ranburr View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ranburr Quote  Post ReplyReply Direct Link To This Post Posted: September/30/2005 at 22:20

Hangfire, I have to warn you, everytime that I have double checked Dale's post.  His facts have always been dead on.  He is defineately my favorite evil genius.

 

ranburr

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