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

Recent content by Eric_D

  1. Eric_D

    BOB Optik ?

    I have a pair of JB133 8x40 9 degree green rubber armoured (GA) binoculars, branded 'Greenkat'. Very nice, pictured. A very popular UK 70s & 80s re-brand in the UK. Their more ambitious offerings are good, some 8x30 wides are disappointing. By contrast, I just dismantled a GA pair 'Paragon UV...
  2. Eric_D

    MOP in Lupinus 6x30

    MOP = Musashi According to MisterDan on the other forum ...
  3. Eric_D

    Duovid Optical Construction

    Just for completeness, there is a diagram in the Company7 Duovid review, showing two (of the) cam slots with opposite-handed (left and right) threads. The image probably comes from Leitz (Leica). All images are the 8x/12x, rather than 10x/15x in the linked review. Presumably it came first. I...
  4. Eric_D

    Pentax VM 6x21 WP Monocular/ 18x Microscope

    If you get the full macro kit, or just the phone adapter, there is an inverted conical eyecup. Edit: thinking about poking it into your cornea, I should call it a 'phonecup', not 'eyecup'. Amazon reviewers do use it with the eye, though. I suspect the intention is you hide the monocular in...
  5. Eric_D

    What is this interesting optical design?

    Oh, the Duovid seems to move two elements or groups along the optical axis, according to a cut-away diagram.
  6. Eric_D

    What is this interesting optical design?

    I don't think it relates to the iRay ZH38 at all (since that has to handle objects at ~infinity) but I can explain the USB microscope. You could ask iRay for the patent, or its number ... You can consider the USB microscope optic as one simple lens (focal length F) that moves between object and...
  7. Eric_D

    Focussing: Just Do It!

    I would interpret it as that the eye is focussed at one metre, while the binoculars focus at ~infinity. Also perhaps the eyes converge to one metre, too. (As in avoiding 'Vergence-accommodation conflict') I guess that reduces the binocular axes' vergence by a factor of 7. Possibly the binoculars...
  8. Eric_D

    Focussing: Just Do It!

    I came to this thread trying to discover whether a topic, about which I was going to launch a new thread, had already been covered or answered. I am still not sure, as the thread is rather non-linear, to say the least. Awesome expertise displayed, but I may post on a DOF thread instead ... The...
  9. Eric_D

    What Porro binocular is Putin using here?

    Another interesting pair ...
  10. Eric_D

    Bushnell's bino-foto 7x50 - remarkable view

    I am very impressed with my pair, compared to Swarovski Habicht SL 7x42. The left eyepiece rotates a little, but I haven't managed to remove it yet. Push in and turn anti-clockwise, like a bayonet lightbulb? Actually the camera, with its own lens, would use the right telescope as an 'afocal'...
  11. Eric_D

    Ross Stepruva Question

    2MB Very much restricts its usefulness, even if you can find such a tiny card. Oh, and you have to put 2xAA inside the fake battery. There are still a couple of dozen on that auction site, up to £40. Sadly, people must buy them ... The binoculars might actually be well-sealed 'Dustproof'. There...
  12. Eric_D

    Ross Stepruva Question

    Although I doubt very much this is made by Canon, it does seem better than much Chinese output. The MX-7000 camcorder has a fake lens, a viewfinder that has to be held at arm's length, and only takes 2MB SD cards.
  13. Eric_D

    Ross Stepruva Question

    Thanks. That sort of hard-to-find info is very useful to collectors, or repairers hunting for spare parts. Interesting too, for historians studying the demise of the British binocular industry, in the face of the Japanese JTII quality control and quality assurance wave. And now the Chinese...
  14. Eric_D

    Ross Stepruva Question

    Another 10x42 Ross "Kensington" of this black-and-white logo outsourced re-badging period surfaced. Looks very like an Opticron model ... that embossed border to the leatherette ... I note Dollond also started badging Japanese binoculars ...
  15. Eric_D

    Which binoculars fall over?

    There is a reference to Ross No.6 Mk.1 4x25 British military binoculars tending to fall over, on miniaturebinoculars.com : https://www.miniaturebinoculars.com/part6/Page4610.htm And a comment by Simon Speirs on Flickr "Dollond (Wray) Standard coated 8x30" suffering if modified to focus close...
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