• 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. O

    Polarized optics in binoculars?

    For uses like that (searching over sea/sun glare), their usefullness is solidly established. Standard massive-improvement. Fishermen use them as well.
  2. O

    Polarized optics in binoculars?

    If you read the (pretty credible) testimonials at the Byfield site, they provide a dramatic difference under conditions of extreme glossy sun-glare, exactly like polarized sunglasses do. The difference is you are losing 15% of the light, not 75% (camera polarizer) or 90%+ (sunglasses). So it's...
  3. O

    Polarized optics in binoculars?

    Is the collimation off...or are those two models? Very James-Bondish....could make a blind man talk about seeing again.
  4. O

    Polarized optics in binoculars?

    Wow..pretty sophisticated. They are taking advantage of polarization that occurs at the surfaces anyway. Form the see glare comments, it isn't completely clear whether it's linear or circular, but at 15% loss, it would be worth cleaning up the 'shiny glaze' at the edges of birds, water, wet...
  5. O

    Polarized optics in binoculars?

    The human eye would see a 75% reduction in bright levels as a small change, physiologically. In bright snowy conditions you would be reducing the blinding effect 2 ways. Of course, brightness with lower contrast is just worse contrast. I remember in optics lab, being asked to rate how much the...
  6. O

    Polarized optics in binoculars?

    Good question... looks like Tiffen's are "2 f-stops": http://www.bhphotovideo.com/find/Product_Resources/polarizerComu.jsp%29 That's about a 75% loss. Yikes. Probably worth getting a used CP filter and checking out 1 barrel. Not for twilight, it seems.
  7. O

    Polarized optics in binoculars?

    I've tried it...the sunglasses dim things a lot, but the effect does happen. But...that's 'linearly polarized'. They are talking about circularly-polarized, though. That would be spoiled a bit going through all your coatings and angles. So....you put the filter in one place early on. front or...
  8. O

    Polarized optics in binoculars?

    Transition lenses allow you to adjust the FL of your eyes, for effective depth of field... at a definite cost in field of view. The job is less important and much more complicated for binoculars, and the loss of field through the long barrel would be pretty harrowing in terms of moving the...
  9. O

    Polarized optics in binoculars?

    Polarizing filters have been in use for a long time now in cameras, so it should help to see what they do there: http://www.cambridgeincolour.com/tutorials/polarizing-filters.htm Some good demonstration pictures. They reduce haze enough to more than make up the losses in increased saturation...
Back
Top