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

Search results

thxpress_search_the_forum Search Opus
  1. S

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

    Did it yesterday and yesterday my color vision was normal. Can't say anything about Zeiss simply because I have no Zeiss - I became allergic to Zeiss in my first days here because a couple of alphadiots spoilt it for me. I originally joined to find info on Zeiss/Leica (zhe djerman glass is zhe...
  2. S

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

    Exactly.
  3. S

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

    Especially intriguing considering the Stiles-Crawford Effect (SCE1) explained by Omid, where the perception of brightness decreases towards the temporal and nasal sides because of the angle of reception of the rods which are placed on the wall of what for our purposes is a sphere (presumably all...
  4. S

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

    Last time I had to wrestle with maths of that sort was during my undergraduate days. I will happily leave this to others. Now where's the popcorn ...
  5. S

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

    Thanks for pointing me at the New Horizons II thread. Engrossing.
  6. S

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

    Saying that the field is small would be the understatement of the year. Swaro's 10x40 is way off the mark at 4 mm exit pupil and only a 40 mil objective. The other 'alphas' have reduced themselves to producing expensive and inefficient roof prisms only, so tbh I am looking straight at Nikon's...
  7. S

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

    I did it like this: set up a chair and my IR-converted camera with a remote release on a tripod in the closet. Sat in the completely dark closet for 30 minutes listening to some music. Switched on my IR flashlight (850 nm, just like the camera), held a steel engineering ruler on my cheek under...
  8. S

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

    This article by Holger Merlitz might help you along.
Back
Top