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

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  1. kimmik

    Two classics side by side

  2. kimmik

    The Apple Digital Binocular, gen1

    Wonder how much zoom the forward facing main cameras can provide, then the headset will be effectively digital binoculars with 120degree AFOV 4k resolution. Three element freeform aspheric eyepieces. Just like camera phone, the first iphone didn't have much zoom capability nor image...
  3. kimmik

    High power binoculars, the less well known meaning

    What is a high power binocular? Most people define it as magnifying power. 15x is higher power than 10x. The other definition is light gathering power - 10x56 has greater power than 10x42, fairly straight forward. But also, 10x56 has greater power than 15x56, due to the greater true FOV.
  4. kimmik

    The most expensive lens system on earth?

    After space telescopes, then arrayed ground telescopes, could this Zeiss be the most expensive lens system on earth? I find it a fun coincidence, that it too has 12 optical elements, like many binoculars. The total light transmission is <1%. Resolution is 5 Terapixels.
  5. kimmik

    Binoculars convention should be Aperture Divide Magnification, not Magnification x Aperture... ?

    Mathematically it makes no sense. What is the point of Magnification multiply by Aperture? There is no parameter as far as I can tell, that is calculated with this multiplication. Whereas, mathematically, Aperture divide by Magnification will correctly calculate the exit pupil, and give you the...
  6. kimmik

    A comparison of prism types, and why the Schmidt Pechan seems to have won the premium binoculars

    The prism is the heart of a prismatic binocular, the most critical piece of the technology that converts an inverted and inaccessible image, to a natural extension of the eye of the expected orientation and light path. This is achieved through reflections, many reflections, especially if one...
  7. kimmik

    Globe effect/rolling ball, there is more to it

    Here is a puzzle for you. Why doesn’t camera viewfinder (dslr, mirrorless, superzoom etc) show globe effect? The distortion is pure rectilinear, which supposedly should cause extreme globe effect. When zoomed in, the magnification can be similar to binocular. The AFOV is pretty good too. So...
  8. kimmik

    Adding close focusing to binoculars, just give them spectacles?

    At the cairo museum I was disappointed to not make use of the CL curio more, for the golden mask of Tutankhamun, mummified specimens of ancient people, and small engraved hieroglyphs behind glass cabinets. Briefly I thought the Victory pocket would be nice, but reminded myself of its size and...
  9. kimmik

    An assortment of binoculars

    Weight bare (g) AFOV (deg) Pupil (mm) Hinge k value Transmission Eye relief ED glass Diopter Waterproof Focus mechanism Closest focus Prism Made in ENO 2x galilean 56 25 10 none angle +++ neutral adequate no none none nil ~0.5m nil UK? unmarked Leica 10x25 trinovid 242 53 2.5 double angle ++...
  10. kimmik

    Transmission spectrum curve, neutral vs natural

    Two otherwise identical telescopes, but different transmission spectrum: Spectrum 1 and 2 will have: Similar brightness 2 will have faint yellow/green tint 1 will be more neutral, but less colour accuracy, like fluorescent light (neutral but less natural) Perhaps binoculars/telescopes...
  11. kimmik

    I am returning the Canon IS 10x32

    After owning Nikon Leica Swaro and soon to arrive Zeiss, I became curious about Canon and wondered if a 10x with electronic IS will add any use. Short answer, the 10x32 is a disappointment to me, even though I only paid 525pounds off amazon. The only wow I got was wow I definitely notice the...
  12. kimmik

    A different set of four hand-held binoculars

    It is no secret who's thread inspired this post - @dorubird's essay made a lot of sense to me and I could see myself with the exact same set of four, but the way things worked out gave me a different but also satisfying complement of binos. The biggest difference other than size, is that...
  13. kimmik

    Curio CL 7x21 and Papilio II 6.5x21

    These are the smallest binoculars I have, with similarities that make them almost identical yet differences that ensure each is irreplaceable. This post is not going to be comprehensive, so please read the excellent comparison by Gijs on the following link...
  14. kimmik

    Light throughput equation

    While twilight factor can guide you on how much twilight detail can be seen, I propose a light throughput equation, which allows you to compare the total photons passed through binoculars if used under the same environment. When your pupils are dilated, this factor correlates with the "wow so...
  15. kimmik

    Swarovski glare/flare is deliberate by design? A comparison with Leica

    This has probably crossed many people's mind as well, why would a premium maker of optics seemingly suffer such a basic flaw. All it takes, is blackening of the optical edges, and tightened baffles to be practically glare-free. Leica does this to perfection as part of their signature look...
  16. kimmik

    Ray Optics Simulation of Swarovski NL, SLW

    To help me understand the optical design of the NL series, I have approximated the design using the online simulator linked below. The design file is attached so you may do your own modifications, including changes to the field flattener lenses, to see its effect on field curvature, field of...
  17. kimmik

    A unified theory: Exit pupil aberrations and Eye position, types of image blackout

    With some experimentation, calculations, this is a breakdown of different types of image black out that seems to me most commonly experienced when roaming the eye around looking through binoculars. SAEP being spherical aberration of exit pupil, prism vignette being the "almond" shape of the...
  18. kimmik

    Is this possible? A hypothetical ultra wide angle binocular with compound eyes

    While not ever going to exist in real life, my brief back-of-the-envelope seems to make it a possible design even if it is difficult to optimise. Combining 7 lenses in a mosaic, with each having their own prisms and 50degree-ish AFOV eyepiece, modified to be hexagonal and lined up nearly...
  19. kimmik

    Collection feels complete… any ideas/suggestions?

    A brief explanation is that I’ve dabbled with astro, bino and camera optics for a while now and this year restarted collecting but more selectively. Didn’t want to put this in the swaro subforum because while I like them, probably better looking elsewhere at this point. Current: 7x21 CL 8x30...
  20. kimmik

    DIY prism shift image stabilisation for spotting scope/telescope/monocular

    Similar to the thread on binocular DIY stabilisation, this is to brainstorm ideas on making an image stabilised spotting scope. https://www.birdforum.net/threads/diy-image-stabilisation-is-for-binoculars.428109/page-4#post-4376202 Difference is there is more freedom to experiment with the...
  21. kimmik

    DIY Image Stabilisation (IS) for binoculars

    This thread is for the do-it-yourself, hacker, tinkerer, who has been curious about image stabilised binoculars. The background for this topic is here: Premium (Alpha) vs Image stabilized By increasing the Moment of Inertia in the image plane (2 axis stabilisation is all you need, can...
    • kimmik
    • Thread
    • canon image stabilized is binoculars
    • Replies: 80
    • Forum: Binoculars
  22. kimmik

    Biggest eyepiece ocular lens - is there bigger than swarovski SLC 8x56 ?

    So looking for something a little different, I’m trying out the 8x56 SLC for two weeks. The thing that struck me the most is the size and flatness of the ocular lens, like a big window vs small window feeling. This is in addition to the huge exit pupil. Measurement of the ocular lens diameter...
  23. kimmik

    Tasco 7800 trinocular binocular/camera hybrid

    Just received this in the mail and thought it might be interesting as a curiousity for fellow members - the only thread where this has been mentioned: https://www.birdforum.net/threads/feedback-please-on-bin-camera.389741/#post-4001936 The FOV is 9.5degrees 7x20, the central lens is 110mm...
    • kimmik
    • Thread
    • antique binoculars tasco trinocular
    • Replies: 24
    • Forum: Binoculars
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