Journalists, and everyone: don't discard film yet

Discussion in 'Digital Photography' started by Unclaimed Mysteries, Jun 19, 2006.

  1. Unclaimed Mysteries, Jun 19, 2006
    #1
    1. Advertising

  2. John McWilliams, Jun 19, 2006
    #2
    1. Advertising

  3. Unclaimed Mysteries

    2 Guest

    "Unclaimed Mysteries"
    <> wrote in message
    news:aWolg.7706$...
    > New Device Disables Digital Cameras
    > http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras


    To disable a camera in a random public place would require more beaming
    disablers than are feasible.

    But it's pretty much true that almost anything digital that can receive can
    be crippled. It's a communication-theory kinda truth.

    Hope this message gets ou
     
    2, Jun 19, 2006
    #3
  4. Unclaimed Mysteries

    Charles Guest

    Charles, Jun 19, 2006
    #4
  5. Unclaimed Mysteries

    J. Clarke Guest

    Charles wrote:

    > On Mon, 19 Jun 2006 03:33:26 GMT, Unclaimed Mysteries
    > <> wrote:
    >
    >>New Device Disables Digital Cameras
    >>http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>
    >>If this is for real, and when it is refined, you can count on this
    >>technology to be "repurposed."

    >
    >
    > I wonder how well it would work through a circular polarizer.


    I wonder how well it would work if the camera wasn't pointed at the "thin
    beam of white light". And that's going to go over _real_ big in theaters,
    some gadget shining a light all over the place every time its artificial
    stupidity (artificial intelligence has not yet been developed, but
    artificial stupidity abounds) thinks it sees a camera. And it seems to be
    tailored to CCDs so I find myself wondering if it will see a CMOS sensor at
    all.

    --
    --John
    to email, dial "usenet" and validate
    (was jclarke at eye bee em dot net)
     
    J. Clarke, Jun 19, 2006
    #5
  6. Unclaimed Mysteries

    J. Clarke Guest

    John McWilliams wrote:

    > Unclaimed Mysteries wrote:
    >> New Device Disables Digital Cameras
    >>

    http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>>

    >> If this is for real, and when it is refined, you can count on this
    >> technology to be "repurposed."
    >>

    > Yes, I saw the creature in "Surface" using that very technology.


    I thought the critter in Surface used an EMP.

    > Now, it'd be used by restaurants to kill cell phone use.
    >


    --
    --John
    to email, dial "usenet" and validate
    (was jclarke at eye bee em dot net)
     
    J. Clarke, Jun 19, 2006
    #6
  7. "J. Clarke" <> writes:

    >I wonder how well it would work if the camera wasn't pointed at the "thin
    >beam of white light". And that's going to go over _real_ big in theaters,
    >some gadget shining a light all over the place every time its artificial
    >stupidity (artificial intelligence has not yet been developed, but
    >artificial stupidity abounds) thinks it sees a camera. And it seems to be
    >tailored to CCDs so I find myself wondering if it will see a CMOS sensor at
    >all.


    From the description, it sounds like it depends on a video camera acting
    like a retroreflector, sending more of the incoming light back in the
    reverse direction from how the light arrived. Ordinary skin and fabrics
    do not produce this directional reflection, but cameras (film cameras
    too, not just digital ones!) do this particularly well if the lens is
    wide open.

    And if you're trying to make a pirate copy of a movie, you've got to
    have the camera lens open all the time, and it's got to be set up to
    capture the whole screen width. So the projector that shines a bright
    flash of light at the camera is probably mounted just above the screen
    (where it would be within the FOV), and it's not difficult to make the
    direct projector beam aimed at the clandestine camera brighter than the
    movie reflected from the screen.

    But my knapsack reflects light back to its source too, because it has
    strips of Scotchlite retroreflector sewn onto its surface. This system
    had better not start shining white light on everyone in the audience
    with a reflective jacket, or knapsack, or shoes, or it will be pretty
    unpopular.

    I don't see this working very well for still cameras. At an event
    taking place in a room, people with cameras could be anywhere. You
    might get a pretty poor reflection back from a DSLR or a P&S camera with
    the LCD display turned off, because the shutter is closed and the sensor
    is not illuminated except just before exposure. And how can you equip a
    room with enough projectors to cover every possible direction a camera
    can be aimed from every possible position in the room?

    Dave
     
    Dave Martindale, Jun 19, 2006
    #7
  8. Unclaimed Mysteries

    Mark² Guest

    Unclaimed Mysteries wrote:
    > New Device Disables Digital Cameras
    > http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >
    > If this is for real, and when it is refined, you can count on this
    > technology to be "repurposed."


    From that description, I don't think it would do a thing against DSLRs,
    since their sensor is not only inactive most of the time, but is also
    completely hidden behind both a mirror and a shutter.

    Live LCD cameras like point-and-shoot still cameras and video cameras would
    be a different matter... But the DSLR should be untouchable by this sort of
    device.

    --
    Images (Plus Snaps & Grabs) by Mark² at:
    www.pbase.com/markuson
     
    Mark², Jun 19, 2006
    #8
  9. Unclaimed Mysteries

    Phil Wheeler Guest

    Mark² wrote:
    > Unclaimed Mysteries wrote:
    >
    >>New Device Disables Digital Cameras
    >>http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>
    >>If this is for real, and when it is refined, you can count on this
    >>technology to be "repurposed."

    >
    >
    > From that description, I don't think it would do a thing against DSLRs,
    > since their sensor is not only inactive most of the time, but is also
    > completely hidden behind both a mirror and a shutter.
    >
    > Live LCD cameras like point-and-shoot still cameras and video cameras would
    > be a different matter... But the DSLR should be untouchable by this sort of
    > device.
    >



    Agree.
     
    Phil Wheeler, Jun 19, 2006
    #9
  10. Unclaimed Mysteries

    Mark Roberts Guest

    Mark Roberts, Jun 19, 2006
    #10
  11. "Mark²" <mjmorgan(lowest even number here)@cox..net> writes:

    >From that description, I don't think it would do a thing against DSLRs,
    >since their sensor is not only inactive most of the time, but is also
    >completely hidden behind both a mirror and a shutter.


    >Live LCD cameras like point-and-shoot still cameras and video cameras would
    >be a different matter... But the DSLR should be untouchable by this sort of
    >device.


    Some P&S cameras keep their shutter closed except for the moment of
    exposure when the LCD display is turned off (it speeds up the shutter
    release delay). So turn off the LCD, switch to using the optical
    viewfinder, and your P&S camera may also become immune to the device.

    It sounds like it's only really useful against video cameras, where the
    sensor *has* to be exposed most or all the time.

    Dave
     
    Dave Martindale, Jun 19, 2006
    #11
  12. Unclaimed Mysteries

    PossumTrot Guest

    "John McWilliams" <> wrote in message
    news:p...
    > Unclaimed Mysteries wrote:
    >> New Device Disables Digital Cameras
    >> http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>>

    >> If this is for real, and when it is refined, you can count on this
    >> technology to be "repurposed."
    >>

    > Yes, I saw the creature in "Surface" using that very technology.
    >
    > Now, it'd be used by restaurants to kill cell phone use.



    There is already such a device (cell phone killer) in use in some theaters
    and restaurants.



    --
    Posted via a free Usenet account from http://www.teranews.com
     
    PossumTrot, Jun 19, 2006
    #12
  13. PossumTrot wrote:
    > "John McWilliams" <> wrote in message


    >> Now, it'd be used by restaurants to kill cell phone use.

    >
    > There is already such a device (cell phone killer) in use in some theaters
    > and restaurants.


    Nice. Any idea of mfg. or name of product? (Besides lead walls.)

    pp

    --
    john mcwilliams
     
    John McWilliams, Jun 19, 2006
    #13
  14. Unclaimed Mysteries

    Bill Funk Guest

    On Mon, 19 Jun 2006 08:55:33 -0700, "PossumTrot"
    <> wrote:

    >
    >"John McWilliams" <> wrote in message
    >news:p...
    >> Unclaimed Mysteries wrote:
    >>> New Device Disables Digital Cameras
    >>> http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>>>
    >>> If this is for real, and when it is refined, you can count on this
    >>> technology to be "repurposed."
    >>>

    >> Yes, I saw the creature in "Surface" using that very technology.
    >>
    >> Now, it'd be used by restaurants to kill cell phone use.

    >
    >
    >There is already such a device (cell phone killer) in use in some theaters
    >and restaurants.


    If in the USA, it's illegal.
    --
    Bill Funk
    replace "g" with "a"
     
    Bill Funk, Jun 19, 2006
    #14
  15. Unclaimed Mysteries

    J. Clarke Guest

    Bill Funk wrote:

    > On Mon, 19 Jun 2006 08:55:33 -0700, "PossumTrot"
    > <> wrote:
    >
    >>
    >>"John McWilliams" <> wrote in message
    >>news:p...
    >>> Unclaimed Mysteries wrote:
    >>>> New Device Disables Digital Cameras
    >>>>

    http://news.yahoo.com/s/space/20060619/sc_space/newdevicedisablesdigitalcameras
    >>>>>
    >>>> If this is for real, and when it is refined, you can count on this
    >>>> technology to be "repurposed."
    >>>>
    >>> Yes, I saw the creature in "Surface" using that very technology.
    >>>
    >>> Now, it'd be used by restaurants to kill cell phone use.

    >>
    >>
    >>There is already such a device (cell phone killer) in use in some
    >>theaters and restaurants.

    >
    > If in the USA, it's illegal.


    Depends on the design. A jammer would be, foil in the building structure
    wouldn't.

    --
    --John
    to email, dial "usenet" and validate
    (was jclarke at eye bee em dot net)
     
    J. Clarke, Jun 20, 2006
    #15
  16. "J. Clarke" <> writes:

    >>>There is already such a device (cell phone killer) in use in some
    >>>theaters and restaurants.


    >> If in the USA, it's illegal.


    >Depends on the design. A jammer would be, foil in the building structure
    >wouldn't.


    If it's a "device", it's a transmitter (jammer). An entirely passive
    Faraday cage is possible, but difficult. The 1.9 GHz signal used by
    most cellphones has a wavelength of about 160 mm (6 inches), so any mesh
    screen would need a considerably smaller hole size than this. Solid
    foil should be OK too, but either way you have to make a good electrical
    connection at all the joints in the screen/foil, all along the joint.
    That's got to be expensive to do during the construction of any
    building.

    Dave
     
    Dave Martindale, Jun 20, 2006
    #16
  17. Unclaimed Mysteries

    Mark Roberts Guest

    Dave Martindale wrote:

    >"J. Clarke" <> writes:
    >
    >>>>There is already such a device (cell phone killer) in use in some
    >>>>theaters and restaurants.

    >
    >>> If in the USA, it's illegal.

    >
    >>Depends on the design. A jammer would be, foil in the building structure
    >>wouldn't.

    >
    >If it's a "device", it's a transmitter (jammer). An entirely passive
    >Faraday cage is possible, but difficult. The 1.9 GHz signal used by
    >most cellphones has a wavelength of about 160 mm (6 inches), so any mesh
    >screen would need a considerably smaller hole size than this. Solid
    >foil should be OK too, but either way you have to make a good electrical
    >connection at all the joints in the screen/foil, all along the joint.
    >That's got to be expensive to do during the construction of any
    >building.


    There's a shielding paint available for this purpose.

    --
    Mark Roberts Photography & Multimedia
    www.robertstech.com
    412-687-2835
     
    Mark Roberts, Jun 20, 2006
    #17
  18. Unclaimed Mysteries

    J. Clarke Guest

    Dave Martindale wrote:

    > "J. Clarke" <> writes:
    >
    >>>>There is already such a device (cell phone killer) in use in some
    >>>>theaters and restaurants.

    >
    >>> If in the USA, it's illegal.

    >
    >>Depends on the design. A jammer would be, foil in the building structure
    >>wouldn't.

    >
    > If it's a "device", it's a transmitter (jammer). An entirely passive
    > Faraday cage is possible, but difficult. The 1.9 GHz signal used by
    > most cellphones has a wavelength of about 160 mm (6 inches), so any mesh
    > screen would need a considerably smaller hole size than this. Solid
    > foil should be OK too, but either way you have to make a good electrical
    > connection at all the joints in the screen/foil, all along the joint.
    > That's got to be expensive to do during the construction of any
    > building.


    Actually, you don't need a Faraday cage. All you need is a reflector
    between the phone and the cell tower. You should be able to demonstrate
    this with your cell phone and a few sheets of aluminum foil (you'll have to
    block all towers in line-of-sight but you won't have to have a full cage).

    You're forgetting that at those frequencies signalling is essentially
    line-of-sight.

    If blocking cell phone signals was as difficult as you make it out to be
    then a lot of people who live in houses with foil vapor barrier would be a
    lot happier.

    --
    --John
    to email, dial "usenet" and validate
    (was jclarke at eye bee em dot net)
     
    J. Clarke, Jun 20, 2006
    #18
  19. "J. Clarke" <> writes:

    >Actually, you don't need a Faraday cage. All you need is a reflector
    >between the phone and the cell tower. You should be able to demonstrate
    >this with your cell phone and a few sheets of aluminum foil (you'll have to
    >block all towers in line-of-sight but you won't have to have a full cage).


    Have you tried to demonstrate this yourself? Diffraction means that the
    signal "leaks" around the edges of the reflector and fills in behind it.
    You get some shadow area behind the reflector, but it's not as effective
    as you imply.

    >You're forgetting that at those frequencies signalling is essentially
    >line-of-sight.


    With respect to large objects like mountains and buildings, yes. But
    with respect to objects the size of a wall or a window, there's a big
    difference between the behaviour of visible light with a ~500 nm
    wavelength, and cellphone radio with a ~160 mm wavelength.

    >If blocking cell phone signals was as difficult as you make it out to be
    >then a lot of people who live in houses with foil vapor barrier would be a
    >lot happier.


    If the foil vapour barrier means that there are some dead spots in the
    house that give poor reception, the people who live in them will be
    unhappy. But that level of attenuation is far from blocking all signals
    to all positions within the building, which is the level of blocking
    we're talking about for restaurants or theatres.

    Dave
     
    Dave Martindale, Jun 20, 2006
    #19
  20. Unclaimed Mysteries

    J. Clarke Guest

    Dave Martindale wrote:

    > "J. Clarke" <> writes:
    >
    >>Actually, you don't need a Faraday cage. All you need is a reflector
    >>between the phone and the cell tower. You should be able to demonstrate
    >>this with your cell phone and a few sheets of aluminum foil (you'll have
    >>to block all towers in line-of-sight but you won't have to have a full
    >>cage).

    >
    > Have you tried to demonstrate this yourself? Diffraction means that the
    > signal "leaks" around the edges of the reflector and fills in behind it.
    > You get some shadow area behind the reflector, but it's not as effective
    > as you imply.


    I live it. It is not necessary to block the signal completely, it is just
    necessary to degrade it enough that the phone doesn't work.

    >>You're forgetting that at those frequencies signalling is essentially
    >>line-of-sight.

    >
    > With respect to large objects like mountains and buildings, yes. But
    > with respect to objects the size of a wall or a window, there's a big
    > difference between the behaviour of visible light with a ~500 nm
    > wavelength, and cellphone radio with a ~160 mm wavelength.


    A lot less than you think.

    >>If blocking cell phone signals was as difficult as you make it out to be
    >>then a lot of people who live in houses with foil vapor barrier would be a
    >>lot happier.

    >
    > If the foil vapour barrier means that there are some dead spots in the
    > house that give poor reception, the people who live in them will be
    > unhappy. But that level of attenuation is far from blocking all signals
    > to all positions within the building, which is the level of blocking
    > we're talking about for restaurants or theatres.


    You're arguing theory, I'm arguing practical experience. Anybody walks into
    my house their cell phone dies. Same at the houses of others I know who
    have foil vapor barrier in the walls. Yes, you _can_ find a location where
    the phone works, but generally speaking people aren't going to be sitting
    on a countertop leaning against a window in a theater. If I _wanted_ to
    close those holes putting aluminum bug-screens in them would do the job
    just fine. And this is not in buildings where any _effort_ was made to
    block cell phone signals.

    --
    --John
    to email, dial "usenet" and validate
    (was jclarke at eye bee em dot net)
     
    J. Clarke, Jun 20, 2006
    #20
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. Dirk BERTH
    Replies:
    1
    Views:
    775
    Moz Champion
    Aug 26, 2004
  2. Test message, please discard

    , Oct 26, 2004, in forum: Microsoft Certification
    Replies:
    0
    Views:
    592
  3. phil~~
    Replies:
    6
    Views:
    1,776
    Francois Labreque
    Nov 13, 2003
  4. JC Dill

    photo journalists discussion group

    JC Dill, Sep 8, 2003, in forum: Digital Photography
    Replies:
    5
    Views:
    371
    JC Dill
    Sep 10, 2003
  5. dennis

    Discard packets on serial line

    dennis, Jul 1, 2007, in forum: Cisco
    Replies:
    0
    Views:
    381
    dennis
    Jul 1, 2007
Loading...

Share This Page