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Thread: Fresnel Lens

  1. #1
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    Fresnel Lens

    This is more a snapshot than anything else, but for those who own a Better Beamer, or have wondered what a Fresnel lens in big looks like, here is an image of the lens of the Pigeon Point Lighthouse near Pescadero, CA. It is a first order Fresnel lens. The "order" describes the size and focal length, and first order used to be the largest with a focal length of 920mm and a height of 2.59m, before someone decided that that was not big enough and built an even bigger one.

    _AH08762 by ahab1372, on Flickr
    Arnt

  2. #2
    Super Moderator Kayaker72's Avatar
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    Think of the bird shots Joel could get with that!!!

  3. #3
    Senior Member neuroanatomist's Avatar
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    Here's one local to me, a close up of the Fresnel lens at Boston Light. Second order, and still in operation.

    Name:  Boston Light.jpg
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  4. #4
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    Great shot John. They had one of those old 1000W light bulbs on display at pigeon point.


    Arnt
    Arnt

  5. #5
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    Btw if someone has a few million USD to spare, they take donations to repair the lighthouse and put the lens back in its original place.


    Arnt
    Arnt

  6. #6
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    Quote Originally Posted by Kayaker72 View Post
    Think of the bird shots Joel could get with that!!!
    Oh yeah! Give me that with a 25,000mm f/4 lens and a really big tripod and I could get great images from a mile or so

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