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Thread: Ancient Lenses

  1. #11

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    Fascinating article!!

    For the lens you own, every thought of finding a way to try it with a camera? :-)

  2. #12

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    I'm preparing an article about the millions of aspherical lenses that have been produced since way, way before earliest memory.
    They are quite mysterious thingies, being opaque, and not uniformly dense. Evidence that they knew how to use radiation other than visible light, and that graduated refractive indexes held no secrets to the people who made them.
    Very many have holes running through them from one end to the other, the purpose of which modern optical science has yet to disvover and explain.
    Others (late ones) are set in metal, with tiny metal tabs and prongs securing their position. The significance of the geometry of these mounts will reveal yet undreamed of depths of humanity and the origins of the universe.

  3. #13
    Mustafa Umut Sarac's Avatar
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    Q.G. ,

    I am an archaeologist and educated from Neolithic to Hellenistic. Are your research era covers more earlier prehistoric works. Humans producing complicated tool making culture more than 2 500 000 years and some made claims which starting this era 3 400 000 years with Lucy.
    I dont know when wheel started to use but it makes possible to use single point lathes. May be this technology sparked from time to time and carried everywhere with shamans.
    At Northern Iraq , There is Shanidar Cave and A Shaman Grave which his skeloton covered with many many drug making flowers more than 40 000 years ago and chemistry is not strange to those peoples also.
    Shaman Tradition is still a relligion from North Western Europe , Russia to Siberia to whole Asia until Korea and Japan among Turks.
    It is even possible to find correlation with Asian modern Turkish alphabets and 16000 year old Cave and Rock painting stylized symbols called Tamgas.
    And Viking Runics have same letters with no exceptiion same as the Altai Rock Carving Writings and We read both of them in Turkish.
    If you need references , I suggest a book by Selahi Diker . Find his English book , 1000 pages and read Etruscan and Sumerian in Turkish. Even an elementary school children who knows Tuırkish can do this way.
    If you need more details , I am ready.

    Umut

  4. #14
    Mustafa Umut Sarac's Avatar
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    Pole Lathe Lens Turning Description

    The pole lathe is a foot operated reciprocating lathe. A cord is attached to a treadle at one end and to an elastic device or spring at the other. The cord is also wrapped around the workpiece for a couple of turns. When the treadle is depressed the workpiece, which is held between two fixed points, rotates towards the cutting tool - when the treadle is released the spring turns it in the opposite direction. The name Pole Lathe is derived from the fact that a long pole was traditionally used used as a spring to provide the return stroke. The pole is still used by some turners but others find alternatives, such as bungee cord, more convenient

  5. #15

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    Umut,

    Thanks for your helpful remarks. I'm sure the article will be a great success.

  6. #16
    Ole
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    Very interesting indeed!

    But - having recently been operated for myopia, "It bears microscopic carvings which could only have been made with, and can only be seen with, a magnifying glass." doesn't quite convince me. Strong myopia can in many ways "replace" a magnifying glass, and I now find myself searching for a magnifying glass all the time where earlier I would just take off my glasses!
    -- Ole Tjugen, Luddite Elitist
    Norway

  7. #17
    Mustafa Umut Sarac's Avatar
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    Ole ,

    Wonderful point.

  8. #18

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    Quote Originally Posted by Mustafa Umut Sarac View Post
    The pole lathe is a foot operated reciprocating lathe. A cord is attached to a treadle at one end and to an elastic device or spring at the other. The cord is also wrapped around the workpiece for a couple of turns. When the treadle is depressed the workpiece, which is held between two fixed points, rotates towards the cutting tool - when the treadle is released the spring turns it in the opposite direction. The name Pole Lathe is derived from the fact that a long pole was traditionally used used as a spring to provide the return stroke. The pole is still used by some turners but others find alternatives, such as bungee cord, more convenient
    Such pole lathes were used, seasonally (by "Bodgers"), to produce "Windsor" Chairs in commercial quantities in Great Britain up until WWII at least, from relatively "green" locally harvested timbers.

    Thanks very much for the very interesting articles on a fascinating topic.

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