• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
Where premium quality meets exceptional value. ZEISS Conquest HDX.

Search results

thxpress_search_the_forum Search Opus
  1. D

    Daft question about low-light performance

    It depends on your age and if you're older your pupils are slower to change with changing light and will not dilate as much in low light and everybody's pupils can be a little different, but you are correct in that some peoples pupils can get down to 2mm in the daytime. "In bright light, pupils...
  2. D

    Daft question about low-light performance

    I would say low light would be 1/2 hour before and after sunset or under canopy or in a dense forest or shaded canyon.
  3. D

    Daft question about low-light performance

    True, but you also have to consider how bright the exit pupil is and that is a function of the binocular's transmission and if your pupils will dilate enough to accept the larger exit pupil.
  4. D

    Daft question about low-light performance

    Not necessarily. It depends on how dilated your pupils are. If you are older and your pupils are only dilating to say 5mm or if you are using your binocular in the daytime when your pupils only dilate to about 4mm, the larger objective will not make any difference because the biggest EP your can...
  5. D

    Daft question about low-light performance

    When you are discussing low light performance in a binocular, you are concerned with two separate parameters. Brightness and Twilight Factor. 1) Brightness First is brightness, which is a function of the size of the binocular's exit pupil and the binocular's transmission. EP or exit pupil is...
Back
Top