IR reflection from snow???

Discussion in 'B&W: Film, Paper, Chemistry' started by stradibarrius, Jan 2, 2010.

  1. stradibarrius

    stradibarrius Member

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    I know that green leaves etc. give the IR effect that we think of in IR shots. Does snow reflect the IR in sunlight???
     
  2. AgX

    AgX Member

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    The reflectivity of snow depends to some extent on internal reflection within the snow.
    Water has a higher absorbance for IR than for visible light. Now it depends to what extent the light is not only reflected by the snow crystals but also transmitted. The more bulk the snow particles get, the greater their filtration effect becomes.
     
  3. jp498

    jp498 Member

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  4. George Collier

    George Collier Member

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    jp498 - sky looks kinda light for IR in your linked shot - what is IR Digital?
     
  5. photomem

    photomem Member

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    A digital camera with the IR filter removed or disabled.
     
  6. AgX

    AgX Member

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    A digital camera with the IR-blocking filter removed is just a panchro-camera plus IR. So the IR radiation is added to the visible wavelenghth. In film photography the blue or even panchro sensitivity is still that great that in typical cases you have to block that by means of a IR-only transmitting filter.
     
  7. Sirius Glass

    Sirius Glass Subscriber

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    You need to add a red #25 or #29 filter to take out the panchromatic portion of the visual spectrum.

    Steve
     
  8. jp498

    jp498 Member

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    Last edited by a moderator: Jan 7, 2010