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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Recent content by AltaVista

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    NL Pure 'problems'.

    In the attached cutaway view of a Zeiss 8X32 T-FL you can see the elastomeric seal rings nicely highlighted in red. These rings are used to seal some of the static parts like the front lens and lens cell and the eyepiece lenses and lens cells as well as the focus drive mechanics for the internal...
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    NL Pure 'problems'.

    An elastomeric o-ring, or other shaped sealing ring (could be a square or X profile ring) would be the most common method of sealing rotating parts for low speed applications. Another type of seal ring called a lip-seal has some advantages and might be ideal in a focus drive to achieve low...
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    NL Pure 'problems'.

    Regarding the NL focuser problem that the OP experienced: The NL is apparently designed to be sealed against water penetration but your particular example seems defective in the quality of sealing. There is probably an o-ring type seal on each end of the focusing drive shaft or some similar...
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    Swarovski NL 8x42 - First Impressions

    I understand your point and agree that the "view" is what matters. However the evaluation of the view by any particular user is highly subjective. The star test is a more objective test and when comparing binoculars it gives a sense of how the binoculars imaging performance might compare under...
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    Swarovski NL 8x42 - First Impressions

    Yes. Some of us use binoculars to look at stars as well as birds (and rocks and trees and insects......) And if you have 20/10 vision (with corrective lenses) it matters a lot. Stephanie PS: Take your time Henry, we are looking forward to your well thought out review!
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    Review

    Good discussion by Bill and Eitan regarding the terminology used by reviewers! The term “flat field” has been bastardized in binocular forums to the point that it is effectively meaningless without additional clarifications. To optics engineers the term “flat field” would naturally refer to...
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    Swarovski NL 8x42 - First Impressions

    Perfection is a hard nut to crack. It is thrilling to many of us that Swarovski has made an effort to advance the performance of the handheld “alpha” class of binoculars to a new, higher level. But, it is clear from some reliable early test reports that Swarovski has not “cracked the nut”...
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    Swarovski NL 8x42 - First Impressions

    If by randpupille design you mean minimizing the pupil vignetting at the edge of the field of view then that would require larger diameter lens elements in some locations which in turn might allow more stray light paths to get through to the observers eye. This is all part of the design...
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    Swarovski NL 8x42 - First Impressions

    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...
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    New Product Introduction Today From Swarovski ?

    Perfectly valid method to hold a binocular. The fingers extended on one hand under one barrel has the advantage of keeping that elbow down against the body and adds considerable stability to the view. Try it if you have not. There are many good ways to handhold. I find it useful to vary the...
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    Swarovski NL 8x42 - First Impressions

    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...
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    Swarovski NL 8x42 - First Impressions

    Thanks Kimmo for the detailed report on the 10X NL. I think you have everyone's attention now in anticipation of getting our hands on the NL. Stephanie
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    Swarovski NL 8x42 - First Impressions

    Wondering the same, how does the 8X42 NL compare to the 10X42 NL? I really need to compare them side by side to decide between the two. I have mostly given up on handheld 10X binocs since I am older than dirt and not as steady as in the past but the trick headrest on the new NL has me tempted to...
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    Swarovski NL 8x42 - First Impressions

    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...
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    Swarovski NL 8x42 - First Impressions

    Your eye is focused at infinity during normal binocular use. So your retina is optically at infinity for a normal person with relaxed vision. The graph paper test would be valid for distortion if the graph paper were at infinity, or at a reasonable distance such as several meters. Stephanie
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