So, when you’re photographing flowing water and you want to get that smooth, cotton-candy type look to the water, how exactly do you do that? For the most part, you won’t be able to reliably get that effect using your cellphone, but there are apps you can get to use with your cellphone that will allow you to capture this effect. The better, and I think, easier choice is to use your dslr for these kinds of shots. All of the photos above were taken with my crop-sensor Nikon. I remember being totally baffled when I first got it and tried to document flowing water, waterfalls and other moving things to get that flowy appearance. This was the first thing I wanted to do and the first thing that caused me to have any real interest in taking my camera out of automatic.
After taking my camera out of auto, I started messing around with shutter speed, because I figured it was the time factor that made all the difference. Well, I was right about that, but that direct approach to slowing down the shutter speed caused me some other problems, like over-exposure. The longer the shutter is open of course, the longer the light has to come in. The water may look smooth and flowy, but you’ll definitely need to “fix the exposure in post”. Sometimes this comes out ok, but usually not.
There are a couple of options you have to fixing this problem in-camera. You can go into full manual mode, setting the shutter speed and the aperture yourself. Some people feel this is always the best choice and that any photographer worth his or her salt should be shooting in manual mode anyway. Most modern dslr’s have a variety of settings you can use other than the extremes of either full auto or full manual. I’m a “middle of the road” type of gal at heart. I do think learning manual shooting is good because it gives you a better understanding of what is called “The Exposure Triangle”, which is composed of ISO (which used to be called ASA and denoted the speed of the film back in the day of film photography), the shutter speed, and the aperture of the lens. See illustration below for “The Exposure Triangle”
When you’ve set your camera in either A mode or S mode, that means you’re choosing the shutter speed in S mode, and the camera will adjust the aperture for you; or likewise, if you’re shooting in A mode, you’ll set the aperture of the lens and the camera will choose the shutter speed for you. This helps take some of the guesswork out of the process. I often shoot in A mode, which allows me to change my aperture on the fly while allowing the camera to figure out the shutter speed for me -one less thing to think about! When I’m in the field, my total attention is on what’s happening around me and I don’t like to spend my time thinking about too many technical variables.
Below is an illustration of what the lens of your camera does depending upon where you have set your aperture, or “F-stop”. These show two extremes, to give you some idea. So, when looking at F/16 you can see that the lens is stopped down to a small point, nearly a pinhole and in f/4, the lens is open almost all the way letting in more light. I know it sounds counter-intuitive, but in photography, the smaller the F-stop #, the more light comes in, and the bigger the F-stop #, the less light it lets in. Clear as mud? OK.
So in an alternative to slowing down your shutter speed, going into full manual mode and setting your aperture, most modern cameras allow you to set one while the camera will set the other. This is my “go to” setting for shooting waterfalls and moving water in general. The bigger number F-stop I use, the less light comes in, which requires more time. Thus, the shutter speed is slowed down allowing for smooth flowy water pictures without over-exposure.
Now everyone’s aesthetic tastes are just a little different and your aperture setting depends on how flowy you want to go. I have found F/16 usually does the trick. You could probably use a smaller number and still get the effect you want, but you should experiment with it. I’ve seen some water pictures where I personally think the slowing was a little too slow, making the water look more like a gas. I personally like mine to look flowy, but natural for my more documentary style.
Other options while shooting to slow shutter speed down include using filters on your lens while shooting. I usually use a radial polarizer which cuts glare and does slow the shutter down slightly on it’s own. Some people really like to use Neutral Density Filters, which slow things down even further, depending on the strength of the filter. Shooting waterfalls in general is best done in the shade, or on a cloudy day because the water can create a lot of glare if it’s in full sun and thereby speed up the shutter speed so you lose the flowy effect.
The best thing to do is to get out and practice until you find settings that do what you want in the way you want them done. In photography, I’ve found that there is always more than one way to achieve any particular result. Have fun!