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Where premium quality meets exceptional value. ZEISS Conquest HDX.

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  1. B

    Effect of Magnification on Light Output from a Binocular

    I am not sure the point you are trying to make. For an extended object that fits within the FOV, the brightness of the object will be the same through a 10x or 8x binocular in your daylight viewing situation. Is the point that you and OP are trying to make that a larger image is composed of...
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    Effect of Magnification on Light Output from a Binocular

    The answer is that twice the light will reach your eye. It will still have the same intensity, the image will just be bigger. By saying equivalent AFOV between 8x and 10x is the same as saying that the 10x true FOV is 64% the size of the 8x FOV
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    Effect of Magnification on Light Output from a Binocular

    Neither of these statements is correct. The same amount of light enters the eye, given a uniform field and equivalent instrument AFOV. This is due to the wider angle of acceptance of the 8x instrument; i.e. it 'gathers' light from an area wider than the the 10x instrument (the area of the FOV...
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    Effect of Magnification on Light Output from a Binocular

    No, if the amount of light per unit area is the same, the total amount of light is the same for any pupil diameter less than the 10x exit pupil. For any larger pupil size the 8x lens receives more light.
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    Effect of Magnification on Light Output from a Binocular

    Good catch- obviously this can’t be the case. His point is not true. The same amount of light per unit area would arrive at the lens as well as at the pupil if the light source was larger than the FOVs (assume equivalent AFOV of the devices).
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    Effect of Magnification on Light Output from a Binocular

    The idea behind a binocular is pretty simple. Start by thinking about how your vision works; Let's say you are looking at a white sheet of paper from 10 meters away. It looks white and has a certain size (lets call this Object brightness = 1 and magnification =1). As you move away from the...
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    Effect of Magnification on Light Output from a Binocular

    It doesn’t make sense to concern yourself with the irradiance at the exit pupil, where if it is more concentrated it is also much more divergent. The light intensity on the retina is always the same (given an ideal 100% transmissive telescope). This would be true for your 7.5 cm circular object...
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    Do you use your Nikon roofs in the rain?

    I’ve used my MHGs in rain and snow many times. I’ve had them for 5 or 6 years now and they still function as new.
  9. B

    Fieldscopes

    This appears to be a Nikon 20/30/38 MC Wide eyepiece. This is probably my favorite of all the fieldscope eyepieces and one of the hardest to get. Unfortunately it appears on your sample that somebody has removed the twist-up eyecup and modified it for digiscoping purposes. If you can manage to...
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    Checking Collimation

    Rafael Ramon Chabos has shared a few easy methods to objectively quantify misalignment of binoculars (and an algorithm to collimate them at home). https://sites.google.com/site/rchamon/home?authuser=0
  11. B

    Zeiss Conquest HD 8x42 v Opticron Aurora 8x42

    I agree with your premise, but my experience is that a CCW to infinity binocular is not a pleasure to use physically because of the focus direction. My other binoculars are CW to infinity, my spotting scope is CW to infinity, and my camera is CW to infinity.
  12. B

    The Zeiss SFL 8x30 compared with select current 8x30/8x32 roof binoculars

    You ought to take the NL, sell it, then buy the SFL and pocket $1k.
  13. B

    Is there an optimum FOV, or is bigger always better?

    It isn’t the first time: This was certainly the case through the 60s and later when various companies were selling Japanese-made wide angle binoculars; the wider the better. There is a site (Christmas.musetechnical.com) that has all the old Sears catalogs. They are really cool to look at, and...
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    Monarch HG vs Conquest vs Viper.

    I have compared them all side by side and I own the MHG. The Conquest and MHG are different but equal optically. I liked the MHG for the FOV, weight/shape, and focuser. The Conquest is heavier and has rubber armor that the MHG doesn’t, the image is colder with a bit more pincushion. This makes...
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    Why are Meopta's so hard to sell?

    Cabela's was selling the x32 Euro HD models for $400 brand new a few months ago and the Cabela's models often sell used for much less than the prices being discussed here. That could certainly reduce the pool of potential B1 Plus buyers.
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    Roof prisms (Svbony SV202 10x42) Chromatic aberration, cushioning, blurring at edge - comparison, example pictures?

    You are expecting way too much out of these binoculars
  17. B

    Old classics!!

    The FL controlled CA very well compared to the conquest, but I liked the ergonomics, contrast, and distortion (Pincushion on the FL seemed a bit excessive) in the conquest. They are both nice, and I bet I would like the x32mm FLs better than the larger ones.
  18. B

    Old classics!!

    I have only looked at the 42mm objective versions, but I definitely prefer the Conquest to the FL.
  19. B

    Recovering from DEET

    After getting tired of paying a lot for the ready-to-use permethrin, I also bought in bulk. I use Martin's 10% permethrin, which I dilute into a spray bottle and apply to clothing. I find that it is extremely effective against ticks, but I still get some mosquito bites (not sure if it is better...
  20. B

    Checking collimation at home

    It is a given (post 1) that using our eyes to assess misalignment is the first step. Correct me if I am wrong, but there is some desire, from OP and others, to remove the subjectivity of just looking through the binoculars to judge alignment. Your suggestion seems to be to use a collimator...
  21. B

    Checking collimation at home

    The method I linked to requires a mirror, flashlight, and piece of cardboard. The collimation can be accurately checked, indoors, in a few minutes. Correcting misalignment takes longer but Rafael’s paper describes how to do that as well.
  22. B

    Checking collimation at home

    Here is a simple and effective way to do it with items you have around the house. I’ve used this method a number of times. https://sites.google.com/site/rafaelchamoncobos5/home/setup-with-mirror
  23. B

    Using DS eyepieces for viewing on a ED82 fieldscope?

    This is the same progression I went through. Now that I have both, deciding between the 30x and 38x is pretty tough. If it is fairly bright and calm it will be the 38, and if its cloudy or rainy and windy the 30. You would certainly be perfectly content just using the 38x universally, I did that...
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    FOV - beyond what value is too much?

    I think just about everybody naturally centers the subject in the field when viewing a single small subject. Our eyes also naturally look around the FOV a bit too, especially with multiple subjects or when things are moving around. Maybe not exactly 'darting' around but for things like watching...
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    FOV - beyond what value is too much?

    Indeed. It has been mentioned a number of times that wide fields aren't very useful because our eyes can't "take it all in" or some such. The ad absurdum extension of this is that our eyes really can't take in more than a fraction of a degree true FOV for detail examination. Our eyes make...
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