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

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  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...
  16. Eric_D

    Vickers Adlerblick

    Resurrecting another old thread ... I can no longer see the original auction listing linked above, but have just bought a 'Vickers Adlerblick 10x42', for £42, as opposed to the £140 quoted there. They are really good at the lower price, but the higher price gets you into Zeiss (even Oberkochen)...
  17. Eric_D

    Perger Prisms

    Perhaps somebody DID make Perger prism binoculars about 100 years before the US patent linked above? I have come across another pair of vintage no-name binoculars similar to these renovated by Potts34 and posted in the vintage thread on the other forum...
  18. Eric_D

    Ross Stepruva Question

    Ah, yes, my memories are not entirely reliable. I was conflating the Pentac with the Aero Ektar. And my contact with Dallmeyer could have been at the end of the eighties. They said records were lost in the war. Might have been at another site. I think it was for an Adon collapsing telephoto...
  19. Eric_D

    Ross Stepruva Question

    Dallmeyer seemed to drop out of the binocular market before WW1 ? Photo from https://www.monocular.info/dallmeyer_rp.htm I think their factory was bombed in WW2, and they were very specialised thereafter. I remember emailing them around 1995 ... Oh. 1863 to 1902...
  20. Eric_D

    Ross Stepruva Question

    Thanks. I shall memorise their contours in case I find some in a charity shop, with the markings worn off ... I remember buying a couple of radioactive 'Spitfire' aero lenses (6-inch f/2.9 ? Dallmeyer Pentac?) from Proops. Still in a metal ammo box somewhere here. DIY bins project? Seems the...
  21. Eric_D

    Ross Stepruva Question

    This page ⬇️🔗 shows new-style logos on paperwork for a Steptron 6001, which actually has old-style logos. Suggests a transition within the same company, rather than selling the name. Or perhaps old stock was sold with the name to the new company...
  22. Eric_D

    Ross Stepruva Question

    A crude test with phone camera vs. Phone and binoculars shows an 85 pixel object magnified to 847 pixels, which is pretty close to 10x. Given pincushion distortion, it won't be constant everywhere. I understand inflation of specs: see 40x60 monoculars on Amazon. I was amused to see a pair of...
  23. Eric_D

    Ross Stepruva Question

    Resurrecting an 11 year old thread... I just bought "Ross London STEPVUE Binoculars 10 x 40 Coated Wide Angle" from that auction site. It is a reuse of the old name, contemporary to the OPs Stepruva. Same black/white logo, JB-4, "T.E JAPAN" on bottom hinge-cap. Nice optically, but eye position...
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