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Thread: Long Exposure Challenge

  1. #21
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    ND filters are neutral density filters. Essentially, they should have a neutral colour balance while restricting the light passing through, and therefore reaching the lens/film plane. They come in different strengths, depending on your applications, so you can eliminate anything from 1/3 stop of light through to the range of 20 stops or so for specialised applications.

  2. #22

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    Originally posted by Jed
    ND filters are neutral density filters. Essentially, they should have a neutral colour balance while restricting the light passing through, and therefore reaching the lens/film plane. They come in different strengths, depending on your applications, so you can eliminate anything from 1/3 stop of light through to the range of 20 stops or so for specialised applications.
    OIC..thanks Jed...are they expensive??

  3. #23

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    Originally posted by kawan
    If I not mistaken..
    you need 1 sec for the train effect
    the time needed for the train to stop to open door is about 7 sec liau..
    to capture the ppl movement you will need another 3 - 6 sec..
    so total atleast 12 sec!!
    how to prevent over expose??
    There is a trick that's commonly used for fireworks and other similar effect.. all you need is a black card and a camera that can set long exposures... I haven't tried this yet in daylight, so I don't know how well it works.

    Set the timing to be about 15s (based on kawan's 12 secs estimate), I would cover the lens with the black card and trigger as the train comes in, remove the black card for about 2 secs to capture the train blur, then cover the lens again until the doors open, then uncover the lens for another 2-3 secs.

    Probably takes some trial and error to find the best times to keep both exposures open... and also some practice to cover the lens fully while not causing camera shake.

  4. #24

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    Originally posted by willyfoo


    There is a trick that's commonly used for fireworks and other similar effect.. all you need is a black card and a camera that can set long exposures... I haven't tried this yet in daylight, so I don't know how well it works.

    Set the timing to be about 15s (based on kawan's 12 secs estimate), I would cover the lens with the black card and trigger as the train comes in, remove the black card for about 2 secs to capture the train blur, then cover the lens again until the doors open, then uncover the lens for another 2-3 secs.

    Probably takes some trial and error to find the best times to keep both exposures open... and also some practice to cover the lens fully while not causing camera shake.
    Was wondering as you cover the lens..won't it capture the motion of the black card covering the lens???

  5. #25
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    Originally posted by Paladin


    Was wondering as you cover the lens..won't it capture the motion of the black card covering the lens???

    worst than that..
    you have to tatally cover the lens.. if not the extra light will excape into the edge of the lens..
    and this will effect in "Camera Shake"

  6. #26
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    Originally posted by Paladin


    Was wondering as you cover the lens..won't it capture the motion of the black card covering the lens???
    nope. it captures stills not video. once light has already "entered" the lens, the images are captured.
    Check out my wildlife pics at www.instagram.com/conrad_nature

  7. #27

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    LOL...and its a 'black card'
    So how can a camera 'see's' black?

  8. #28

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    There are 2 concerns..

    I you'd had to do it fast enough, or part of the frame will be brighter than the other.
    And you've to try to cover fully without causing camera shake.. (but I'm assuming that once you've got the lens reasonably covered, camera shake won't show up much since the camera 'sees' black and therefore doesn't record anything..

  9. #29

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    Originally posted by Shadus
    LOL...and its a 'black card'
    So how can a camera 'see's' black?
    My concern is during the motion of covering the lens with the black card..will it be captured??

  10. #30
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    You have to be fast. I heard that My Mediu format friend uses this techique for his long exposures as well.

  11. #31

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    take the underground MRT stations, it'll be darker there, at F5.6 would prabably need like 4s second exposure to get bright enough images...

  12. #32
    Yakuza
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    Hi,

    Kawan very nice shot, esp can see the poster about asking people to move back, nice touch :-)

    Don't people look at you suspiciously for taking photos at MRT esp after that Yishun Mrt affair?

  13. #33

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    Originally posted by Yakuza
    Hi,

    Kawan very nice shot, esp can see the poster about asking people to move back, nice touch :-)

    Don't people look at you suspiciously for taking photos at MRT esp after that Yishun Mrt affair?
    True..true...better layoff the MRT for the moment or I may end out having my Pic on the newspaper instead of taking the pic myself!

  14. #34
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    Do street photography style lo.... at underground station with wire release... Hang the camera round your neck, lean on wall. Trip the shutter with wired release and then pray and wish you don't move or get stomp over by the morning rush...

  15. #35
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    heheh..
    I done it w/o a tripod too..
    just use the multiple expose.. that way, you'll able to get few shot that is minimum cam shake..

  16. #36

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    Originally posted by YSLee
    Use f/22 and a ND4 filter.
    what is a ND Filter?

  17. #37
    Midnight
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    Originally posted by shawntim
    what is a ND Filter?
    Neutral Density filter. It uniformly reduces the light entering the lens by a specified number of stops.

  18. #38
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    Originally posted by shawntim


    what is a ND Filter?

    http://photographytips.com/page.cfm/35


    hope this helps

  19. #39

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    Originally posted by shawntim


    what is a ND Filter?
    Uh, it was explained about 15 posts up.

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