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Thread: Long exposure for waterfall - any alternative for ND filters?

  1. #1
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    Default Long exposure for waterfall - any alternative for ND filters?

    I would like to know if anyone has tried this:

    Without an ND filter, use minimum aperture and lowest ISO setting, mount camera on tripod and take multiple shots of the waterfall. If each shot is 1/250 sec, take a total of 20 shots for a total exposure of 1/4 sec.

    In PS, stack all the 20 shots and do an average.

    Would that blur the water enough to mimic the long exposure achieved with ND filters?

    Any thoughts?

    - Roy
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    Interesting idea. No reason it should not work.

    Don't ask why, ask why not!

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    yeah, quite interesting.

    but will it result a stacks of freeze water droplets instead of a smooth water flow from a longer exposure? maybe can make the shutter even more slower than 1/250 with the possible highest(minimum) aperture.

    maybe somebody can try

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    In the film era, I remember another technique related to photographing water that results in interesting rainbow colours in the flowing water. The trick is to do 3 exposures on the same frame, using R, G and B filters for each exposure, and compensating for each exposure such that the final exposure is correct.

    Things that are stationary throughout the 3 exposures will come out with the correct colur.

    The water, on the other hand, is moving and thus appears different for the 3 exposures. So the combination of the R,G and B for the water alone does not align and thus results in the rainbow colours.

    In the digital age, just take 3 shots and blend the R, G, and B channels from each shot to form a new picture, and you should get the same effect.

    Try this technique on a glass of 7-up and you will get multi-coloured bubbles in the transparent drink.

    Hope to see some posts here that are inspired by this...

    - Roy
    As complexity rises, precise statements lose meaning and meaningful statements lose precision.

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    Originally posted by luisg
    yeah, quite interesting.

    but will it result a stacks of freeze water droplets instead of a smooth water flow from a longer exposure? maybe can make the shutter even more slower than 1/250 with the possible highest(minimum) aperture.

    maybe somebody can try
    Probably stacking 1/10 sec exposures will do a better job.
    As complexity rises, precise statements lose meaning and meaningful statements lose precision.

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    I have tried the following

    Aperture : f16
    Shutter speed : 1/1000 sec
    Number of exposures : 16 on single frame (to get 1/60, if you want slower shutter speed you have to calculate it accordingly)

    Instead of waterfalls I tried this on the waves. The result was not bad.

    Alternatively you can try 1/500sec and 8 exposures which should be good. I didn't try this.

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    Originally posted by Madhivanan
    I have tried the following

    Aperture : f16
    Shutter speed : 1/1000 sec
    Number of exposures : 16 on single frame (to get 1/60, if you want slower shutter speed you have to calculate it accordingly)

    Instead of waterfalls I tried this on the waves. The result was not bad.

    Alternatively you can try 1/500sec and 8 exposures which should be good. I didn't try this.
    Cool! Will you post the picture - in the Travels forum?
    As complexity rises, precise statements lose meaning and meaningful statements lose precision.

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    I have it on slide and I haven't scanned it. I'll post it soon.

  9. #9

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    Originally posted by roygoh

    In the digital age, just take 3 shots and blend the R, G, and B channels from each shot to form a new picture, and you should get the same effect.

    Try this technique on a glass of 7-up and you will get multi-coloured bubbles in the transparent drink.

    Hope to see some posts here that are inspired by this...

    - Roy [/B]
    Hi...
    How to blend R,G,B channels from 3 shots?
    I suppose you do this in photoshop or something.

    Thanks

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    Originally posted by romeobravo
    Hi...
    How to blend R,G,B channels from 3 shots?
    I suppose you do this in photoshop or something.

    Thanks
    Yes, you have to do that in Photoshop.
    As complexity rises, precise statements lose meaning and meaningful statements lose precision.

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    how to do that?
    pardon my ignorance...

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    too fast a shutter speed may not create a silky effect.... subject might turn out to be too distinct....e.g.

    Pic taken by Okeo from DPReview Fuji Talk Forum using the S602Z:
    Last edited by mpenza; 10th April 2003 at 10:27 PM.
    Check out my wildlife pics at www.instagram.com/conrad_nature

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    Originally posted by mpenza
    too fast a shutter speed may not create a silky effect.... subject might turn out to be too distinct....e.g.

    Pic taken by Okeo from DPReview Fuji Talk Forum:
    Yes, I agree. My initial example of 1/250 was probably a bad example.

    The shuttle speed for each frame should be slow enough to create some blurr of the water, such that when multiple frames are stacked, there is better chances of creating a silky effect.
    As complexity rises, precise statements lose meaning and meaningful statements lose precision.

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    Actually, it's a technique I use frequently and it's something I do often side by side even when I can use a slow enough shutter speed. 1/250 is not fast by any means.

    It presents a reasonable proxy of the painterly effect although the effect is substantially different to warrant shooting both. Hard to describe it but it's not surprising; it is what you'd probably expect to get if you understand how exposure works. Possibly akin to a very fine pointilisation style with the water, instead of being smooth it's more like very fine flowing sand.

    Sorry I don't have a direct comparison up. I did before but that was on my Asiaphoto site and, as I've just checked, that's long since been drunk up by the Internet black hole.

    But yes, it works. No, it's not a waste of film. And yes, it's certainly worth trying.

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