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

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  1. Alexis Powell

    What is more important transmission or exit pupil size as we age?

    I am a photographer and devote a bit more consciousness than the average person to trying to be aware of the color temperature of light, esp. when dealing with mixed light sources. Nevertheless, like everyone, my eyes/brain aim for 'auto white balance'. However, I usually look through bins for...
  2. Alexis Powell

    What is more important transmission or exit pupil size as we age?

    Did the test. Normal. I see a greenish bias to my Zeiss 8x25 Victory Pocket. It is obvious in use and is also especially easy to see when looking through the bins backwards held against a white paper. Is this result interesting? Does is solve any arguments? Glad if so. --AP
  3. Alexis Powell

    What is more important transmission or exit pupil size as we age?

    To do what? To achieve similar visual acuity at randomly selected reading distances? Maybe. To see things when light levels are exactly low enough that the (population average) amount of age-related decline in pupil dilation would be exactly compensated by 3 times more light? OK, that would make...
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