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Swarovski NL 8x42 - First Impressions (1 Viewer)

To simulate your eye with the graph paper test you would need to put a zero distortion lens in front of the graph paper (to image the graph paper at infinity, like your retina). Then you would have great test. But, it is hard to find a substitute for the compact lens/retina/brain visual system that corrects for distortion over a large FOV.

Stephanie

Sorry, but I still don't get it. Why not take the graph paper as representative of the effective function of my cornea (which, though domed, and together with my lens, projects a flat image as approximately focused on my curved retina)? The path from cornea to retina, is a constant across all binocular evaluations, so not of interest. I'm also not terribly interested in how well my visual system corrects for distortions. That too is essentially a constant. I'm interested in whether a bin can provide a view that is imperceptibly different from what would be a naked-eye view, only magnified 8x prior to delivery to my eyes.

--AP
 
Many thanks for your detailed and knowledgeable observations, kabsetz. Given the apparent advantages of the NL headrest, it'll be interesting to see if after-market versions start to appear...
 
Thanks very much Kimmo. I think that tells me all I need to know. I just pre-ordered an 8x42, something I don't take lightly.

As for the distortion photos, AltaVista is correct about avoiding very short distances between the binocular eyepiece and the grid target, like one or two inches, but in my experience the grid doesn't need to be anything close to infinity to avoid significantly distorting the results. I use the longest distance that the largest available target allows, which can be as close as about 25 cm for letter sized graph paper, to about 0.5 m for a set of mini blinds to about 3 m for the clapboard wall on the back of my house.

Henry

PS. Alex, what you'll see if the distance between the eyepiece and the grid is too short, like 1-2 inches, is usually an increasing bulge of barrel distortion the closer the eyepiece comes to the grid. I have one binocular with essentially zero rectilinear distortion in this test at any distance over 10 cm (Fujinon 8x30 FMT-SX). That one actually shows increasing pincushion distortion as the eyepiece nears the grid.
 
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"Thanks very much Kimmo. I think that tells me all I need to know. I just pre-ordered an 8x42, something I don't take lightly."

Henry, how about adding the 10X42 to the order also?

Andy W.
 
Viewing towards the sun with the sun some 10 degrees above the horizon, there was some veiling glare towards the bottom of the image. This mostly stayed at the edge or, at most, bottom third of the image, but was immediately noticeable to me when comparing with the Canon which is one the best I have used in this regard. At around sunset, I viewed some more, and here again the NL had more veiling glare than the Canon. As it stayed away from the image center, it did not bother me too much, but this was the one area where the NL was less than state-of-the-art in my view.


Kimmo

I am was afraid the glare control was sub-par, somewhat typical of Swaro. This problem could be exacerbated in the 12x due to its smaller EP.
 
I am was afraid the glare control was sub-par, somewhat typical of Swaro. This problem could be exacerbated in the 12x due to its smaller EP.

Yes, that does appear to be one stone left unturned. I'm hoping that the larger exit pupil of the 8x42 will allow less veiling glare to enter the eye most of the time, but non-image forming light from internal reflections near the edge of the exit pupil is never a desirable thing for the best possible image contrast, even during lighting conditions when it's not causing actual veiling glare.
 
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What is your justification for that claim? It doesn't feel so to me, and there's evidence to the contrary, as in this recent thread:
https://www.birdforum.net/showpost.php?p=4009330&postcount=210

If you have normal vision (or if you are viewing with glasses) your eyes are most relaxed when viewing objects at infinity.

When viewing through a binocular or telescope you would focus so that the image of the viewed object (regardless of its distance) is focussed by the objective in the focal plane of the eyepiece.
The rays emanating from the eyepiece would then be parallel, placing the apparent image of the viewed object at infinity.

John

PS:- I don't agree with Omid's theory.
 
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"Your eye is focused at infinity during normal binocular use."

What is your justification for that claim? It doesn't feel so to me, and there's evidence to the contrary, as in this recent thread:
https://www.birdforum.net/showpost.php?p=4009330&postcount=210

That quoted post does not seem to account for the fact that my IPD looking through binoculars at an infinity target, is the same as without binoculars (and different to looking at something at 1m). Not to mention that without my glasses I can't focus anything at 1m and with binoculars I can see fine at any distance.

An interesting question. Perhaps worthy of its own thread.
 
What is your justification for that claim? It doesn't feel so to me, and there's evidence to the contrary, as in this recent thread:
https://www.birdforum.net/showpost.php?p=4009330&postcount=210

Getting off topic for this thread but I will answer your question:

It may be that some people naturally focus a binocular with their eyes accommodated to the 1 meter object distance (1 diopter) mentioned in that thread. I have not researched the studies that indicate a relaxed “dark focus” of the eye is 1 meter on average and so I would not want to dispute that claim without more research. Maybe it is the case but my experience is much different. It seems to me that one diopter accommodation does not make a large difference to the use or performance of the binocular in any case.

I know that I tend to naturally focus adjustable eyepieces to very near zero diopters, especially binoculars in the field in the daytime when the real object is at a distance my tendency is to focus at zero diopters. Same is true for astronomy at night and in the past I have noted other observers that did the same with large aperture fixed mount binoculars with individual focus and diopter scales on the eyepiece. I have several dioptometers to check the diopter scales. That was past experience, currently, at an advanced age, my accommodation range is well under 1 diopter and with corrective lenses I can assure you that my eyes are close to stuck at infinity. Not that I am very happy about it! For critical viewing I wear single vision Zeiss corrective lenses for the best quality of imaging.

More important to the current discussion is which to choose? 8X42 NL or 10X42 NL? I will leave the very interesting 12X42 NL to the steadier handed birders. My first binocular as a youngster was a 16X50 (a bad choice) but I could hold it very, very steady.

Stephanie
 
Yes, that does appear to be one stone left unturned. I'm hoping that the larger exit pupil of the 8x42 will allow less veiling glare to enter the eye most of the time, but non-image forming light from internal reflections near the edge of the exit pupil is never a desirable thing for the best possible image contrast, even during lighting conditions when it's not causing actual veiling glare.

Yes, regarding glare control the 8x42 should fare better, on the other hand it can be expected to have more pincushion distortion than the 10x but I hope only slightly more (to avoid a "rolling bowl" effect).
 
Other brief observations on the 10x NL.

Viewing towards the sun with the sun some 10 degrees above the horizon, there was some veiling glare towards the bottom of the image. This mostly stayed at the edge or, at most, bottom third of the image, but was immediately noticeable to me when comparing with the Canon which is one the best I have used in this regard. At around sunset, I viewed some more, and here again the NL had more veiling glare than the Canon. As it stayed away from the image center, it did not bother me too much, but this was the one area where the NL was less than state-of-the-art in my view.

Kimmo

Thank you Kimmo, great insights, that made me cancel my order on the 10x NL.
 
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If you have normal vision (or if you are viewing with glasses) your eyes are most relaxed when viewing objects at infinity.
That is the disputed claim. It seems unlikely from a biological point of view, and it doesn't feel that way to me... though I wonder what I would have said when my distance vision was sharper.

I have doubts about Omid's theories also, but when I performed his experiment with a camera I found that I was viewing distant objects with the bino focused to form an image at about 2m. I admit I've given insufficient thought to the validity of the experiment.

Edit: I meant to give a link to the thread from that point on including the experiment, not just a single post from Omid.
Here it is: https://www.birdforum.net/showthread.php?p=4009330#post4009330
 
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That is the disputed claim. It seems unlikely from a biological point of view, and it doesn't feel that way to me... though I wonder what I would have said when my distance vision was sharper...

Having been a photographer since the good old days of manual focus film SLRs, I recall that the technical reports in Modern Photography and Popular Photography always listed the apparent distance to the viewfinder image of each camera under review. The distance for most camera models was around 1 m. I asked several "experts" why it wasn't standardized at infinity and was told that a closer distance was somehow more relaxing based on the behavior of the resting but active eye. Now, with aging eyes that don't do so well with close focus, I have a hard time understanding how that could be the case, but that was what I was told at the time.

--AP
 
That is the disputed claim. It seems unlikely from a biological point of view, and it doesn't feel that way to me... though I wonder what I would have said when my distance vision was sharper.

I have doubts about Omid's theories also, but when I performed his experiment with a camera I found that I was viewing distant objects with the bino focused to form an image at about 2m. I admit I've given insufficient thought to the validity of the experiment.

Edit: I meant to give a link to the thread from that point on including the experiment, not just a single post from Omid.
Here it is: https://www.birdforum.net/showthread.php?p=4009330#post4009330

A binocular is an afocal device. You can't project its image on to a plane surface (film or sensor) as you can with a camera lens.
In a binocular the image is formed by the objective and lies between the objective and the eyepiece.
Users with normal (or corrected) vision would adjust the focusser so that the light cone from any point on the image would emerge from the eyepiece as a parallel bundle.
The short-sighted would adjust the focusser so that the image lay inside the focal plane of the eyepiece and the emerging light bundles from a point of interest in the image diverged. Conversely, the far-sighted would adjust for a converging light bundle.
The binocular "focuses" the point of interest either by moving the eyepieces fore and aft (most Porros) or by shifting the focal point internally (most roof prism bins) by means of a weak lens (can be positive or negative).

In the viewfinder of a reflex camera the image is focussed on a ground-glass screen so that the object of interest in 3-dimensional space can be focussed sharply by the objective. As the distance from the eye to the ground-glass screen is usually too short, a corrective lens is used to increase the apparent distance.
On some cameras this might be as little as 1 m but the far-sighted would then require an additional corrective lens, or a dioptre adjustment.

John
 
Nice preliminary review of the 12X42 NL on Allbinos:

https://www.allbinos.com/index.php?art=179

Very positive first impression except for non-optimal stray light control. Disappointing stray light leak outside the exit pupil.

This shows the difficulty of designing a complex binocular optical system which is a balancing act and compromise even when the retail price is $3K. Light baffling becomes more difficult as the FOV is increased and there are practical size and weight limits on the final configuration.

Will be very informative to see photos of the exit pupils on the 8X42 and the 10X42NL as well as to get more user reviews on real world stray light control on the NL binoculars.

Stephanie
 
I'm seriously thinking about canceling my pre order of 10X42 NL due to allbinos report, if the binocular have poor stray light control i am gonna keep my Noctivid.

Baffling can be tricky on wide angle bins agree but leave areas with weak blackening? why ?

They spend 30 million euro developing this new model and still not perfect or better than competency.

Perhaps it is a good idea to wait a while, Swarovski is always improving its product, perhaps in future models they will fix this issue.
 
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Nice preliminary review of the 12X42 NL on Allbinos:

https://www.allbinos.com/index.php?art=179

Very positive first impression except for non-optimal stray light control. Disappointing stray light leak outside the exit pupil.

This shows the difficulty of designing a complex binocular optical system which is a balancing act and compromise even when the retail price is $3K. Light baffling becomes more difficult as the FOV is increased and there are practical size and weight limits on the final configuration.

Will be very informative to see photos of the exit pupils on the 8X42 and the 10X42NL as well as to get more user reviews on real world stray light control on the NL binoculars.

Stephanie

Stephanie,

Do you know if stray light control is made inherently more difficult due to Swarovski's generous randpupille design ?

Glare is a widely acknowledged shortcoming of the 4mm exit pupil 8x32 SV, which also has one of the easiest eye placements and tolerance for alignment that I have seen in such a 'small' format bin. (I wear glasses for short sightedness, and back the eye cups out just a smidge from fully down).







Chosun :gh:
 

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