New Fuji camera creates new laws of physics

Discussion in 'Fuji' started by Robert Feinman, Aug 7, 2003.

  1. There is a new four page ad for the Fuji E1 digital camera appearing in photo
    magazines this month.
    It shows a pair of ray tracing diagrams comparing the "old" way light
    transverses a lens with the "new" way invented by Fuji.
    The new way light leaving the lens has all the rays parallel so that they strike
    the sensor at 90 degrees. There is no divergence as the rays approach the
    corners. The old way light spreads out as it leaves the lens.

    The only way light emerges parallel from a lens is if the subject is at the
    focal point.
    Perhaps the new Fuji only takes pictures at one (very short) distance?

    If they want to claim something about their lens design (less vignetting,
    perhaps), why not say that instead of making up phony lens diagrams.
     
    Robert Feinman, Aug 7, 2003
    #1
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  2. Marketing and advertising people don't always check their ideas with the
    technical people in the company - the ones who know.
     
    Marvin Margoshes, Aug 7, 2003
    #2
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  3. Robert Feinman

    Tony Spadaro Guest

    Tony Spadaro, Aug 7, 2003
    #3
  4. Robert Feinman

    Matt Clara Guest

    The only type of light I know with (nearly) parallel rays is called a laser.
    Sometimes known as collimated light.
     
    Matt Clara, Aug 7, 2003
    #4
  5. Robert Feinman

    Luke Guest

    Ever heard of sun light? As near to parallel as makes no difference in most
    situations.

    collimated light is not a laser.

    A laser produces light in which the photos are in phse with each other. That
    remains true even if the beam is spread so that the paths are no longer
    parallel.

    Luke
     
    Luke, Aug 7, 2003
    #5
  6. Robert Feinman

    Luke Guest

    No doubt the marketers screwed this up slightly, I havn't seen the advert
    but this sounds very like a kind of field flattener. These lenses are added
    to telescopes to improve sharpness at the edge of an image when taking
    photographs.

    They work by increasing the angle at which light strikes the sensor (CCD or
    film) towards the edge of the image to reduce bluring.

    If I recall my astronomy lectures correctly the focal length on some of
    these lens varies along the radius so your standard optical equations are
    not going to give you much insight into their functioning.

    I guess fuji have come up with some way of making this useful in a compact
    camera but I doubt its going to revolutionise photography.

    Luke
     
    Luke, Aug 7, 2003
    #6
  7. Robert Feinman

    ZZ Guest

    eDigital Photo shows the Olympus E1 SLR showing light rays
    impacting the CCD in parallel. Is this it?
    Gene Gene http://www.photoprojects.net
     
    ZZ, Aug 7, 2003
    #7
  8. Robert Feinman

    Rudy Garcia Guest

    Collimated light doesn't require a laser, in fact there have been
    optical benches using collimated light long before lasers were invented.
    You are confusing coherence with collimation.
     
    Rudy Garcia, Aug 8, 2003
    #8
  9. Robert Feinman

    Bruce Murphy Guest

    Collimation is a property of *some ways of generating laser light* and
    even then it's not perfect collimation. Since most laser profiles are
    gaussian anyway, the ray-optics concept of collimation is one of these
    kindegarten (or undergraduate) lies-to-children.

    B>
     
    Bruce Murphy, Aug 8, 2003
    #9
  10. Physics is the study of frictionless elephants whose masses may be ignored.

    David J. Littleboy
    Tokyo, Japan
     
    David J. Littleboy, Aug 8, 2003
    #10
  11. Collimated light doesn't require a laser, in fact there have been
    optical benches using collimated light long before lasers were invented.
    You are confusing coherence with collimation.[/QUOTE]

    The other way to get collimated light is to throw away the uncollimated
    parts. I.e., use a very small aperture. Not always the most convenient
    for action photography...
     
    David Eppstein, Aug 8, 2003
    #11
  12. Robert Feinman

    mike II Guest


    It's because the forces of goodness and light have kept them at bay. Any
    system that's been up and running crash free for over twelve billion
    years is just fine the way it is.




    mike
     
    mike II, Aug 8, 2003
    #12
  13. Robert Feinman

    Bruce Murphy Guest

    The other way to get collimated light is to throw away the uncollimated
    parts. I.e., use a very small aperture. Not always the most convenient
    for action photography...[/QUOTE]

    It can be argued that this really doesn't do what you think it does,
    thanks to the magic of diffraction and image formation.

    If you took a lens a put some sort of infinitely narrow perfectly
    absorbing honeycomb-type mesh (that was quite deep) behind it, then
    you'd get (very little) collimated light. Pinholes just won't do it.

    B>
     
    Bruce Murphy, Aug 8, 2003
    #13
  14. Robert Feinman

    Bruce Murphy Guest

    But at least they're only hypothetical elephants.

    B>
     
    Bruce Murphy, Aug 8, 2003
    #14
  15. Robert Feinman

    Luke Guest

    there are perfectly feasable ways of making well enough colimated light for
    most practical purposes. Indeed youcould use tube witha mirror at one end
    and a very slightly transmissive mirrored surface at the other end.

    You can put a normal light in there and you have made a collimated source in
    just the same way a laser is made collimated the only difference is you
    haven't made the light coherant.

    Luke
     
    Luke, Aug 8, 2003
    #15
  16. Robert Feinman

    Browntimdc Guest

    Coherent light.
     
    Browntimdc, Aug 8, 2003
    #16
  17. Robert Feinman

    Dreamer Guest

    "Assume a spherical elephant of uniform density..."

    D
     
    Dreamer, Aug 8, 2003
    #17
  18. It can be argued that this really doesn't do what you think it does,
    thanks to the magic of diffraction and image formation.[/QUOTE]

    Yes, I severely oversimplified. Thanks for the clarification.
    The point I was trying to make was the "(very little)". You need more
    than a pinhole in your device, but the amount of light you get is
    similarly small to a pinhole.
     
    David Eppstein, Aug 8, 2003
    #18
  19. There is no physics problem. Anyone can add pixels. The trick would be to
    add resolution, and their ads seem to claim they do.

    For years, Fuji has struggled to get ahead of Kodak, instead of copying
    them. Tilting the sensor 45 degrees is at least a novelty.
     
    Marvin Margoshes, Aug 8, 2003
    #19
  20. Actually, there *is* a lens design that does this - it's called
    telecentric. The idea is to put a stop in an appropriate place inside
    the lens so that light reaching a particular portion of the image only
    uses the part of the lens rear element which is directly (or almost
    directly) above that place on the focal plane.

    It's not magic, but it's also not what you want in most circumstances.
    It means the lens has to be physically larger than the image format, and
    it also wastes a lot of light (the f-number will be rather large).

    I've read about a telecentric lens being used on an optical printer (for
    film special effects). This would allow the operator to adjust image
    focus without changing image size at the same time. It's also used in
    making measurements: you can get telecentric loupes for measuring stuff.

    Dave
     
    Dave Martindale, Aug 9, 2003
    #20
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