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Photography Question 
Lynda Driscoll
 

Neutral Density Filter and 'Frothy' Water


I was told a neutral density filter will create a "frothy" look to my waterfall pictures. But how do I choose which one to use?


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7/14/2005 7:59:06 PM

 
Brendan Knell
BetterPhoto Member Since: 4/17/2005
  The reason it will give you the a frothy look is because it forces your camera to use a slower shutter speed, so a tripod is a must. About choosing a ND filter, it depends on how bright the scene is. So my guess would be to just choose a good medium, but that may be wrong. Or if your budget allows, you could buy a high one and a low one and one in the middle.


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7/14/2005 10:19:18 PM

 
Joe Jarosz   Hi Lynda,
Basically the ND filter is like a pair of sunglasses. They cut the light hitting the film much like sunglasses cut the light hitting your eyes. So for taking pictures, you can leave your lens open longer (use longer shutter times)to get the right amount of light on your film and that has the effect of making the water look misty, ethereal, frothy. They come in various qualities and densities. Tiffen, Hoya, B+W, there's more too. Tiffen are usually the most economical. They also come in stops. I'd go for a 3 stop. They might also be called .09. That's a good one to start with. Also make sure you know the size of your lens, because they come in different sizes - for example, my Canon 70-200 is a 77mm. Hope this helps.


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7/15/2005 5:04:30 AM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  Neutral density filters are rated by the amount of light reduction provided. Either as number of stops (each stop = 1/2 as much light) or by factor (each 0.10 = 1/3 stop).
For example, if your exposure is f/11 and 1/125, but you want a shutter speed of 1/8 without using a smaller aperture, then you need 4 stops (1.2 factor) of light reduction. You can do that with a single filter, or combine 2 or more filters that add up to 4 stops.


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7/15/2005 7:09:09 AM

 
Lynda Driscoll   Thanks to everyone who responded. Wish me luck!!!


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7/16/2005 8:15:56 PM

 
Joe Jarosz   good luck


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7/16/2005 8:46:06 PM

 
Maria Melnyk   If it's not sunny outside and you use slow film and a small aperture, you may be able to get that slow shutter speed without that filter.
Oh, and here's a "Good Luck" from me too.


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7/19/2005 12:20:54 PM

 
Shirley D. Cross-Taylor
BetterPhoto Member Since: 1/7/2001
Contact Shirley
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  Maria is right. The best time to shoot waterfalls is on overcast days. If you are using 100 speed film or slower, and a small aperture (f11 to f22) you will easily get the silky or 'frothy' look.


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7/19/2005 1:12:03 PM

 
Kevin Elliott
BetterPhoto Member Since: 8/10/2004
  The trick is to get the shutter speed down, somewhere between 1/30th and 30 secs, depending on the speed of the water and what you want to achieve. Use a tripod. Really, you need a selection/set of ND filters - 1,2 and 3 stops. Then you can stack to get the effect you want. Remember also that a polarizing filter doubles as a 2 stop neutral density, so that can help as well. I've used a 3 stop (0.9) ND with polarizer to get the effect I wanted with ISO50 film. A starting exposure would be to expose for the highlights, plus 1 stop. Bracket around this value. Watch for vignetting/light fall-off in the corners if you stack too many together!


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7/19/2005 11:54:55 PM

 
Maria Melnyk   Yes, a polarizer will work for this purpose, but there might be some nice reflections in the water that you might like to show, and a polarizer will eliminate them. However, it will saturate the colors more, so you can use it to advantage also. Try it both ways.


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7/20/2005 11:48:05 AM

 
Kevin Elliott
BetterPhoto Member Since: 8/10/2004
  The polarizer won't necessarily eliminate these reflections - you can adjust it so that it leaves them there! Take a look at this which was polarised for the sky, but not for the lake... http://www.betterphoto.com/gallery/big.asp?photoID=575916&catID=&style=&rowNumber=41&memberID=81822


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7/20/2005 11:34:30 PM

 
Lynda Driscoll   thanks again everyone...keep them coming!!


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7/22/2005 10:33:11 AM

 
Bob Cammarata
BetterPhoto Member Since: 7/17/2003
 
 
  Sample 1
Sample 1
Nikkor 180 mm, Provia 100,...1 second exposure
© Bob Cammarata
Nikon FM2 Manual E...
 
  Sample 2
Sample 2
Nikkor 180 mm, Provia 100, 1/2 second
© Bob Cammarata
Nikon FM2 Manual E...
 
  Sample 3
Sample 3
Nikkor 180 mm, Provia 100, 1/2 second
© Bob Cammarata
Nikon FM2 Manual E...
 
 
As others have already mentioned, cloudy days (or deep shade) are your best possible scenarios. It's quite possible to achieve up to a 1 second exposure times at ASA 100 when in deep shade. The attached photos were shot a few days ago shaded under a canopy of forest trees without any filters.


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7/22/2005 6:12:34 PM

 
Lynda Driscoll   Bob, those pictures are hot!!!! How would you have done them if it wasn't cloudy?


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7/24/2005 5:16:53 PM

 
Bob Cammarata
BetterPhoto Member Since: 7/17/2003
  Thanks Lynda.
It was actually quite sunny that day but the dense canopy created enough shade to get those slow speeds. (You can see in the third example how a peak of sunlight illuminates a portion of the rock in the foreground.)
This is best attempted on small creeks where you can get real close to the falls or rapids to crop out any sunlit portions of the water. There will be literally 3 to 4 stops difference between the sunlit portions and those in the shade. You must be careful not to let the sun hit ANY of the rapids in your composition during long exposure times, or you will get a wash-out of that portion of the frame.
On cloudy days, the light is diffused and more even so you won't have to worry as much about getting hot-spots.
In either scenario, your best bet is to meter manually off the frothiest part of the rapids and open 1/2 stop over that setting. All three of the attached photos were metered that way.
Bob


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7/24/2005 7:49:48 PM

 
David A. Bliss  
 
 
This picture was shot with an 8x neutral density filter.


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7/24/2005 8:06:34 PM

 
David A. Bliss   Ok, I guess I don't know how to post a picture in the forum that I already have in my gallery, so here is the link

http://www.betterphoto.com/gallery/dynoGallDetail.asp?photoID=1056251&catID=&style=&rowNumber=1&memberID=119007


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7/24/2005 8:08:42 PM

 
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