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

Recent content by kimmik

  1. kimmik

    Two classics side by side

    Here are some crops of areas of interest. Henry you nailed the Optolyth, 30x60, with the smaller eyepiece. The prism is a porro with a rhomboid prism to center the image, as John has described. I did take apart a 30x80 optolyth for cleaning and they seem to have the same prisms. And...
  2. kimmik

    Two classics side by side

  3. kimmik

    Focus to infinity for short-sighted users

    was the diopter set to 0 on the noctivid? mine (and presumably all) noctivid easily makes 4D with the diopter at 0. with the diopter at 4, there is still a tiny bit over overdrive so 4.5/5D max total correction is about right.
  4. kimmik

    TIR, prism choice and its effect on image quality

    TIR in optical fibre lets light run many kilometers without a boost. That is in the order of billions of TIR reflections. Even then it is probably the glass attenuation that reduces signal, rather than imperfection in the TIR. Of course even superconductivity is not actually perfection...
  5. kimmik

    The Apple Digital Binocular, gen1

    Virtual visit has been the point of binoculars all along, isn't it? No need to stop at 1x virtual visit. The magnification can be set arbitrarily. Its just a question of how good the main cameras are. like the situation on phones.
  6. 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...
  7. kimmik

    High power binoculars, the less well known meaning

    Handbook of optics, Bass 2009, reference manual for the optical society of America: "The amount of flux which can be transmitted through a prism or other optical element depends on both its angular aperture and its cross-sectional area. The greater the amount of flux which can be transmitted...
  8. kimmik

    Optics misused Terminology.

    Totally lost me there I’m afraid 😂
  9. kimmik

    High power binoculars, the less well known meaning

    Thread '- The nominal luminous power of the binoculars:' https://www.birdforum.net/threads/the-nominal-luminous-power-of-the-binoculars.384516/
  10. 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.
  11. kimmik

    Optics misused Terminology.

    I'd like to add a parameter to the original list, that is not well known but is a deciding factor for me when choosing bino: Etendue per mass, also known as light throughput per mass. A binocular with high etendue per mass is the equivalent of a car with high power to weight ratio. Another...
  12. kimmik

    CA always seems to mean lateral, is longitudinal really not seen?

    Its funny the diagram got the rays wrong for lateral CA. Most people can’t tell though. The simulated image is correct.
  13. kimmik

    CA always seems to mean lateral, is longitudinal really not seen?

    Long-CA: ca arising from lateral part of exit pupil Shows most when your pupil is off center Lat-CA: ca arising from lateral part of image Shows most when your gaze is off center Long-CA: error of focal plane improved by stopping down the objective or the eye pupil Lat-CA: error of...
  14. kimmik

    Canon EOS 80D always slightly "fuzzy"

    Panning
  15. kimmik

    Canon EOS 80D always slightly "fuzzy"

    The first images show motion blur plus out of focus. Last image is out of focus. Assuming you can get good shots of static object: Lens optics are ok Try servo mode focus plus burst Up the ISO Stop down a bit Slightly faster shutter speed Check IS modes on lens, some are not good with panning...
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