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  1. #1

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    "Enlarging" with a fresnel sheet magnifier?

    Just curious, has anyone tried creating something of an "enlargement" using a fresnel sheet magnifier (such as one seen here)?

    I envision something like a contact print, but with the sheet magnifier between the negative and the photo paper. If so, what does the end result look like? I would imagine there would be some distortions, etc. Perhaps I'm not searching correctly, but I can't find any examples of this directly.

    It's an idle question, but I've seen these sheet magnifiers in stores a few times, and often wondered what the effect would be as an "enlarging" device.
    i can't wait to take a picture of my thumb with this beautiful camera.

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  2. #2
    Mustafa Umut Sarac's Avatar
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    Put a print under this plastic fresnel magnifier ,whatever you see, will be whatever you get from contact print. I think fresnel magnifier plastic will focus the source light in to the paper and you will see dark and light circular rings.

    Umut

  3. #3

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    Fresnel lenses are fine for concentrating light but cannot be used for imaging. The circular lines will also be reproduced.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  4. #4

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    Quote Originally Posted by Gerald C Koch View Post
    Fresnel lenses are fine for concentrating light but cannot be used for imaging. The circular lines will also be reproduced.
    Not true. A fresnel lens (like most other lenses) has a focal length. You can use it for enlarging, but not for a contact print.

  5. #5

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    Quote Originally Posted by Matthew Rusbarsky View Post
    Not true. A fresnel lens (like most other lenses) has a focal length. You can use it for enlarging, but not for a contact print.
    Sorry but you are wrong. http://science.howstuffworks.com/question244.htm

    Fresnel lenses can be used in enlargers but only between the light source and the negative. As I said they are not good for imaging.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  6. #6
    E76
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    Umm, fresnel lenses can and have been used for imaging! They bring rays of light to a single point of focus, forming a real image, and they do have a focal length. Like all lenses the quality of the image depends on the quality of manufacture and most fresnel lenses are not built to very high standards. In this regard they are not very useful for imaging. Other than that, there's no reason why you can't use one!

  7. #7
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    All I can say is that they do indeed form an image. I think it'd be cool to make a fresnel lens camera.

    Someone with a Anniversary Graphic (focal plan shutter) should make a glass lensboard with a fresnel mounted to it.
    If you are the big tree, we are the small axe

  8. #8
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    I've used a cheap fresnel as part of a box camera. Works fine, if a bit difficult to focus - the reading magnifier I used had a very short focal length, making it very sensitive...

  9. #9

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    The following quotation is from one of the many web sites discussing the use of Fresnel lenses. "Even though each groove or facet brings light precisely to a focus, the breaking up of the wavefront by the discontinuous surface of a Fresnel lens degrades the visible image quality. ... Fresnel lenses are usually not recommended for imaging applications in the visible light region of the spectrum".

    You could use a Fresnel lens of very high quality but the image is still degraded. You can ignore civil laws but you cannot ignore the laws of optics. I could post many more quotations but what would be the point.
    Last edited by Gerald C Koch; 07-25-2011 at 06:29 PM. Click to view previous post history.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  10. #10
    michaelbsc's Avatar
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    So the answer is "Yes it will work."

    Not well, but it will work. For that matter, a lawn mower can be used as transportation device. It isn't a good fit, but it will work.

    I rather like Chris's idea to make a fresnel "lensboard" for a Speed. Might be better than a Holga.
    Michael Batchelor
    Industrial Informatics, Inc.
    www.industrialinformatics.com

    The camera catches light. The photographer catches life.

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