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Slow shutter, whispy waterfalls.


anesh

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I've tried using a small apperture, iso 100 and slow shutter to get "whispy"

waterfalls but the picture is always terribly over-exposed. The 30d's top LCD

panel has a display indicating exposure and even in fairly low light I can't

seem to slow down the shutter enough to get the desired effect without the

overexposure. I've seen many great pics on this site where such effect is

successfully applied. How do I do it?<div>00JuZN-34932084.jpg.0b1aa3983f5a9b049d18dabb18b4fff9.jpg</div>

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You need some neutral density filters. They are filters that uniformly reduce the amount of light entering the lens without affecting the colour (if their are good and truly neutral). They are sold by the number of 'stops' worth of light they reduce. You can stack them to add the effect of multiple filters together.

 

I personally like B+W in general and I'd suggest buying 77mm size filters and a step-up ring for whatever lens you are using so you don't end up buying them again for a lens with wider threads (note: this will prevent the use of a bayonet-mount lens hood on lenses with thread size smaller than 77mm).

 

You'll probably want at least a one-stop and a two-stop. Maybe also get a three-stop. B+W's numbering a little strange. The following table is from adorama's page:

 

B&W Neutral Density filters are available in the following strengths:

? .3 (2X) #101 Reduces the light one f-stop.

? .6 (4X) #102 Reduces the light two f-stops.

? .9 (8X) #103 Reduces the light three f-stops.

? 1.8 (64X) #106 Reduces the light six f-stops

? 3.0 (1,000X) #110 (ten f-stops) & 4.0 (10,000X) #113 (seventeen f-stops) are for astrological and sun studies.

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AH, ND filters. Thanks a lot. I was jumping up and down wondering why I can't get it right. My lenses are a Canon 24-105mm f/4 IS and a Tokina 12-24mm f/4. Both can use 77mm filters. Which strength of ND filter is most commonly used.
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Yup, you need an ND filter. I generally use an 8x (.9) ND filter, because in a pinch, it will usually let me get a shot for the internet in full daylight, which I'd normally avoid.

 

A polarizer would probably help with some shots, as well, and in a pinch you can use one as a weak ND filter. I don't normally end up needing the polarizer, because I try and go out early on overcast or cloudy days.

 

The most important things you need are your tripod, a remote release, and an ND filter. Equipment-wise, it is an easy feat. Don't expect dazzling shots in full sun at noon, it just won't happen. Don't expect to get the hang of it the first time, it may take a few weeks to learn which shutter speeds work best with different volumes of water. Generally, I follow the rule that the less water you have, the longer the shutter speed, because it makes smaller waterfalls more dramatic. Larger waterfalls tend to look better at very high shutter speeds, which captures the raw power. Your style may vary.

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ND filters will certainly get you longer shutter speeds giving you a greater whispy effect, but I'm not sure ND filters are going to help you with your overexposure problem.

 

You didn't really get into any detail about how you're metering or setting your exposure. Is it only the white water that's overexposed and all the surrounding greenery looks ok? Could be a greater contrast range than your sensor can handle. I've run into that many times since switching to digital. Waterfalls that Reala would have handled easily end up with the water blown out and overexposed, even on overcast days. The only compromise I've found is to take a couple of exposures, one for the surroundings, and then one for the water and blend them together later. (Actually, many for the water, with different shutter speeds, but all properly exposed for the water so I can choose the best one afterwards).

 

Alternately, are you setting the exposure manually, and cranking the dial farther even once the exposure indicator has gone by +1 and +2 and is flashing? Concentrating solely on shutter speed without regards to the overall exposure? If you are, then stop it! That's why your photos are overexposed. If this is what you're doing, they'll still be overexposed even with an ND filter.

 

Anyway, like I said, it seems you have two separate problems. Getting a long enough shutter speed, and dealing with overexposure. An ND filter is the solution for the first, and setting the exposure properly is the answer for the second.

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i agree with the above post. an ND filter will only allow you to slow down the shutter speed, but the overexposure problem is a function of metering. i've had problems in similar situations, but what i do now is make sure i separately meter all parts of the scene. water, foliage, rocks, sky... etc. then, knowing the exposure latidude of your film or sensor, make the appropriate exposure decision. relying on matrix metering for such shots is a gamble, so i would not do that. careful metering is the only way to correctly expose in such situations. a filter, unfortunately, is not the solution. I am assuming, of course, that you are not shooting in direct, overhead sunlight as you will have a very tough time getting a proper exposure, let alone a good looking photo, in such light.
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A polarizer is preferred vs. ND filters, if the pola will give enough exposure reduction. Otherwise, use the polarizer PLUS an ND filter if you need more. The reason is that the polarizer will reduce some of the reflections from wet rocks and vegetation, giving an overall increase in saturation which ND filters can't do.

 

Also, always shoot white water on cloudy days.

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Frank and Anish are right on. If you're trying to expose the white water correctly, set your

spot meter on it, increase the exposure by 1.5 to 2 stops, and use that for the entire scene.

If the rest of the scene looks too dark at that point, then you are trying to record an exposure

range greater than your sensor/film can handle. There are several digital techniques to

address this (blending of two or more shots taken at different exposures, blending of two or

more RAW version set at different exposures), but perhaps the best solution is to shoot when

the contrast in the scene is not so great (earlier/later in the day, cloudy conditions, when

shade envelopes the scene, etc.).

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Heres my beginner answer:

 

I took this last week. It was cloudy and about 1 hour before sunset. I used 1 second

shutter speed, 18f, 100 ISO and obviously a tripod. It was fairly dark. 5pm in the winter on

a cloudy day. I couldn't imagine being able to take it on a sunny day.

 

Its a river, but I'd imagine it would look similar if the water was vertical :)

 

Oh, and and I used by Rebel XT with the kit 18-55 lens. And no fancy filters, just a UV.<div>00JvOX-34943784.jpg.2ea0aa47ac89d3ccd803df356d4cc5a6.jpg</div>

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I got to agree with Alan. An ND isn't going to help you much unless you're trying to even out light intensity in scenes that are somewhat segmental. In your case, that shot in particular, a polarizer would have been your best bet. It would've reduced much of the glare coming off the moving water, thus cutting down significantly with the hot spots problem your having. ND's are usually used for toning down skies that are too bright for the foreground. A polarizer is also going to give you slower shutter speeds by about 1.5-2 stops.
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NDs that tone down skies that are too bright for the foreground are a special kind of ND filter

-- a graduated (or split) ND filter. The ND material is on part of the filter, while the rest of

the filter is clear. That's not what Anesh is after.

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Well ND filters are great, when you have to much light even for small apertures. I normally use a polariser, that cuts down 2 stops and helps with the glare.<p>

The pic you used as an example must have also some post processing like the one I use for similar subjects. In the following example (<a href = "http://www.photo.net/photo/5485278&size=lg">http://www.photo.net/photo/5485278&size=lg</a>) I used the shadow&highlight tool to get out some more details from the water, just like the same way I see in your example (very fine white flowing water lines and detail).

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  • 1 year later...

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