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

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  1. Ignatius

    New but probably wrong insight about lowlight

    Relative brightness is arrived at by EP squared. Therefore an 8x32, a 6x24 and a 10x40 all have the same relative brightness since all have an EP of 4 mm. However, the 10x will give you more resolution than the 8x and the 6x. (Btw there is an interesting paper on the human eye and resolution by...
  2. Ignatius

    New but probably wrong insight about lowlight

    Maybe sometimes one can arrive at the same conclusion by different routes. Maybe some people need things explained in a certain way so they can understand them. There are quite a few people here with profound knowledge of optics, physics, etc. Not everyone who wants to understand some of the...
  3. Ignatius

    New but probably wrong insight about lowlight

    Aaah ... your eyes must be different from mine. My pupils do not move when I look around while keeping my head still - my whole eye(ball) moves. I did not know that pupils could move independently from the rest of the eye. Learn something every day.
  4. Ignatius

    New but probably wrong insight about lowlight

    Does that mean the pupil dilates and contracts or the pupil oscilates (as in nystagmus)?
  5. Ignatius

    New but probably wrong insight about lowlight

    Thank you. Surprisingly, the paper is from 2013.
  6. Ignatius

    New but probably wrong insight about lowlight

    Since one can measure transmission as a percentage of light exiting versus entering an optical system as per DIN ISO 14490-5, one can also take a photodetector to measure light quantities, as photons trigger an electrical signal. That signal is measurable or countable. Ergo one could compare...
  7. Ignatius

    New but probably wrong insight about lowlight

    You're almost there, ReinierB. But it isn't solely the objective aperture that decides how much light reaches your eye, but also the magnification. Both combine to give you something called the exit pupil, and the closer that correlates to the diameter of your dark-adapted own pupil, the better...
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