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

Recent content by Charlie Yardbird

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    Checking Collimation

    For an eccentric objective collimation, is the eccentric supposed to slide around the lens and the lens remain still, or is the eccentric supposed to grip the lens and go around as a unit? I'm working on a Swift Hunter 8x30 with a plastic eccentric, and if the retaining ring is loose enough to...
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    Checking Collimation

    I would hire a machinist to make a collimator for me, but none of the setups on the net have sufficiently accurate information (ie measurements on a diagram or blueprint) for the machinist to follow. And SurplusShed doesn't have big lenses, I've looked. Unless I don't know how to search their...
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    CZJ EDF 7x40 Roof Prism Binoculars

    Does the glass darken from gamma or neutrons? I don't understand why the tritium would be hazardous, unless they painted bare tritium and put the phosphor in the reticle lines. Usually both are encapsulated in a glass phial.
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    USA, Maryland, January, similar to downy/hairy woodpecker but entire top of head red

    Warmed up to 60 F yesterday, 40 today. Did not see her.
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    New APC 42 Stabilized

    Is the Kite PM an older version of the APC model? I see it on their site but no prices, as if out of production. I have Zeiss Conquest HD 8x32 and 10x42. The APC is the same price zone as a Conquest HD 10x32, which would be lighter than the 10x42 and probably just as good in normal light...
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    Copyright of optical system? Why no replicas of high grade binos?

    In the near future, it will be possible to train a robot to disassemble vintage binoculars. Perhaps they could remove the original glass and insert modern glass with better properties. But would that have any appeal? The fun in vintage is the workmanship that you can feel when using the tool...
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    8x42 vs. 10x42 Binoculars

    I have a Conquest HD 10x42 that I keep on a tripod aimed at the birdfeeder. When looking elsewhere, I'm always comparing various vintage binoculars to the Conquest 8x32. The Conquest is brighter in less than full light, but not necessarily sharper. The tripod mounting plate is a quick...
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    Checking Collimation

    What exactly does strabismus do that hinders... whatever sort of collimation tests were being talked about? Inability to focus on a pinpoint without eyestrain... makes you perceive two points even when the optics are perfect?
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    Checking Collimation

    My IPD is only 53mm, so I presume that I will not get accurate results from methods like defocusing a star, or moving back from the ocular when looking at a pinpoint, due to lack of Spacial Accomodation? Most full size binoculars only go down to an actual 55-54mm. I like wide field binoculars...
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    Checking Collimation

    Your book suggested using a Fresnel lens, which turned out not to work. It also says a lens made from inexpensive glass will work (since color correction is irrelevent), but I have been unable to find an 8" or larger example. You also mention that a telescope will work, but I presume that the...
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    USA, Maryland, January, similar to downy/hairy woodpecker but entire top of head red

    But this below freezing weather is all the way down the east coast. Not many insects this time of year. I saw predicted temps as low as in Fargo N.D. !!!
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    USA, Maryland, January, similar to downy/hairy woodpecker but entire top of head red

    It must be a yellow-bellied sapsucker female. I have NEVER seen one before, and am surprised to see it in the winter. The other day we got the super cold weather and 3" of snow and I have not seen her. If the sap freezes up, what else can she eat? Have not seen her at the birdfeeder or...
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    USA, Maryland, January, similar to downy/hairy woodpecker but entire top of head red

    We get hairy & downy woodpeckers at the suet. This guy is girdling my holly tree. It is two stories high & maybe 30" away from a second story window. At the height of the window he is making rounded rectangles 2cm x 2-4cm, not very deep, all around, for a vertical span of say 8" - its a thin...
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    Swift Tyrol 15x60

    Sounds like a common configuration to me. How were you trying to free the frozen parts - a pair of strap wrenches, after soaking in penetrating oil? It looks like there is a crack in the "threaded sleeve" which I refer to as the helical. If you can free them, you may be able to fix the crack...
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    Recommendations for good binoculars for smallish IPD

    I'd kill for an IPD that wide. I'm 53-54mm wide. I find that using wide angle classic porros helps me percieve a single image instead of two partial images. For current production, the Zeiss Conquest HD is stated as 54mm minimum IPD
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