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  1. #21
    Marco B's Avatar
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    Quote Originally Posted by Ole View Post
    But I would be extremely sceptical about interpolating anything to do with the bedrock of Norway. I've worked here as a geologist for 25 years, and there are daily surprises! I think Statens Strålevern might need a little bit more geological competence in their numbers - if the oil boom ends, I'll send them a note.
    Ole,

    Please note this was several years ago, but:

    That was exactly what I told him! Actually, my tool (a kriging spatial interpolator) showed that there was NO spatial relationship BETWEEN points with a 100% random nugget variance. This essentially means that the dataset (a very good one with over 10.000 measurements) may NOT be interpolated.

    However, that doesn't mean there isn't a spatial or better said statistical relationship between soil/rock types and Radon measurements. It just means that any two points close together have no spatial relationship. Realizing this, I figured this is simply caused by the fact that soil / bedrock types tend to vary over relatively short distances with one bedrock type being replaced completely by another, meaning that two houses separated by just 100 meter, might have totally different, and spatially unrelated, Radon levels.

    Such data may never be interpolated...

    I finally advised the guy to forget about a spatial interpolation, which simply is not allowed with such a dataset and 100% nugget variance (this was difficult for him to accept, like many other people, spatial interpolation of point measurements is often considered as the "holy grail" in GIS. "If I can interpolate it, it will be good...")

    I than advised him to try and statistically correlate soil / bedrock type with Radon levels in a normal statistical package, like SPSS. Simply by determining at what bedrock type, based on a geological map of Norway, the measurements were made, and to input that data in the statistical package together with the Radon levels. And maybe even include possible other variables as well, like building material of the houses or possible information about ventilation etc.

    If that would show a statistical relationship between soil / bedrock type and Radon levels, he could than reclassify his geological map of Norway based on low / high Radon risk or levels to get to a country wide map, which was what he was after...

    I don't know if he finally did this, (he sounded actually a little bit desperate at the point I told him he wasn't allowed to interpolate the fantastic dataset collected over years), but I hope so because with such a huge dataset, you can do some very interesting statistical analysis, just not interpolate it.

  2. #22

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    Quote Originally Posted by John Kasaian View Post
    I had my Aero Ektar checked by the nuclear medicine department at the local hospital and got similar results. Just for curiousity they also tested the lens in the home made box I constructed and it blocked all measurable radiation and so that is what I store it in.
    What is it? A 6"x6" x6" cardboard postal carton lined with pieces of "Wonderboard" a cement impregnated fiberglass backing left over from when I installed a tile floor in the kid's bathroom.
    Talk about opening 'Pandora's Box'
    Mark Layne
    Nova Scotia
    and Barbados

  3. #23

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    Radioactive Ektar

    I actually just bought 2 Aero Ektars (Went a little bid happy and won both on ebay !) The Bokeh is amazing...opens up some really creative opportunities.

    I think you get more radiation sun bathing !

    Very Cool Glass !

    Dennis

  4. #24
    Marco B's Avatar
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    Yes, they do seem to be capable of some remarkable images. The Pandora box is actually quite empty, as you can read from my original post and all the comments thereafter, about the only thing you probably better shouldn't do, is store your new lenses under your bed...
    My website

    "The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.

    "I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978

    "Analog is chemistry + physics, digital is physics + math, which ones did you like most?"

  5. #25

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    Great for portraits but I usually use mine one stop down from wide open, if not two. I know this probably negates the idea of using an aero-ektar in the first place but with the DOF being so shallow, it's very easy to end up with a fuzzy portrait with a sharp nose!

  6. #26
    KennyMark's Avatar
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    I ran into a seller at an antique fair this past weekend with a nice one for sale. It seemed to have some sort of hazing or filming on the rear element so I presume that was the effect of aging spoken of here. The seller was asking $450 U.S. for it. Not knowing anything about it at the time, I thought it was a bit much for a lens sans shutter, even one that fast. He mentioned the radioactivity as well.
    If you call it a "prime lens" because it's a fixed-focal length (i.e. not a zoom lens), then as Inigo Montoya said so eloquently, "You keep using that word. I do not think it means what you think it means."

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