Lens Slice for anamorph camera

Discussion in 'Camera Building, Repairs & Modification' started by Mustafa Umut Sarac, Jul 31, 2008.

  1. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Hello ,

    Can We use a lens group slice as a camera lens If we produce a thin slice of a complex multi element lens group and make 360 turn in anamorphic pinhole - we are not using pinhole - camera ?
    My english is weak.
    I am asking that :
    As you know , there are many expensive lens glasses at the market and everything would be more interesting if you make some artificial errors and corrections at the curves of glass elements .
    I have a kodak roentgen lens with tons of glass.
    I can make metal thin molds and fill the molds with glass powder and liquid mix.
    Than make a melt in enamel oven for 1 minute and voila , you have a extreme thin slice of a multi element lens.
    I am thinking to put this lens in a dark cylinder and put a film inside the cylinder.
    Than turn the lens 360 degree and make the image !
    Does it work ?

    Best ,

    Mustafa Umut Sarac
     
  2. AgX

    AgX Member

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    "Conventional" slit scan cameras use a rotational contructed lens plus a slit in the film plane. In your concept it is the other way round. The effect would be the same (with the exception that the slit would most probably deliver a more sharply limited slit image, what could influence the effective exposure time).

    But I don't see the benefit of your idea, except for savings in optical material. You would save maschining in one direction, but still have to make fine curvatures in the other.

    But perhaps I'm slow on the intake again.

    Edit:
    Savings in weight surely will have an effect. But then I could also slice down a rotational constructed "off the shelf" lens.
     
    Last edited by a moderator: Jul 31, 2008
  3. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    It would be very fast and cheap to manufacture may be A5 size lens.
    As you know , cnc machining a 2d thin mold is very cheap and precise.
    I want to find a oven and try ! Ok , I am member of enamel group , let me ask them. Will it be crystal clear or not ?
     
  4. Someonenameddavid

    Someonenameddavid Member

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    Slice of lens

    wouldn't there be a big problem with internal reflections on the air/glass interface on the long sides of the slice: as the slice rotates, total internal reflection would cause obscuring flare.

    David
     
  5. AgX

    AgX Member

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    David,

    the flare problem would be much less than in a round less, simply because there would be much less lens.
    (To be precise, one should take into acount that one would use slit light shade with a classical panoramic camera and thus reduce flare too.)


    Mustafa,

    I have to correct myself (again you had a thoughtprovoking idea...):

    There would not be an aperture (speed) problem of that slice lens. As there only is a slice to be exposed at a time there is only a slice of aperture needed.


    I thought of another obstacle, namely diffraction which would be induced be a very small slit mask (needed to form that slice).
    However,

    -) when using film one could make a slit mask that actually lies on the film. Then there would be no space into which light could be diffracted.

    -) when using an electronic sensor of the CCD type or so one would not need a slit mask at all.
    In case of a swing (slice) lens type of panoramic camera one could arrange the seperate lines of the sensor in parallel to the plane of the slit lens (or rather the virtual slit) Then one only would need to readout the very lines line after line while the small strip of light passes them. No mask would be needed as only a single line is read at a time. (Well, the sensor plane must of course be bent; something very impractible...)
    In case of a rotating type of panoramic camera only a single-line sensor must be used, which is read out repeatedly while the camera rotates.