Light is the one thing every photograph has in common. In fact without it you have nothing. So as photographers we are always on a mission to control or use the light, sometimes by adding in additional light and other times by reducing it. In this photo I wanted to get a slow shutter speed and so that meant reducing the amount of light entering the camera. That’s where a Neutral Density (ND) filter comes in really handy. Basically it’s like putting very dark sunglasses in front of the lens. (In a pinch you could actually try that, too). The one I used here is a 9-stop ND; it’s really dark! In face it is so dark in the viewfinder you can’t really see anything and focusing is just not possible.
Getting around this problem is easy enough; place you camera on a tripod, set the focus to manual and then focus about 1/3 of the way into the scene. With the focus set it is now just a matter of screwing the ND filter onto your lens. You can use a calculator to figure-out the exposure or just count backwards from where it exposed without the ND on. That is easier than it sounds! If it was exposed nicely at 1/60th at f22 then dial-back the time 9 stops from there. If that sounds all too confusing then just slow it down and try a few test shots until you get it right. Given that you’re not using film, the trial and error approach is not a bad one!
Some things to keep in mind; use the best quality ND you can afford and you may see some vignette at the corner of the image. I usually either crop the photo or use Photoshop/Lightroom to remove it.
One more thing to note is that these slow motion water shots look best when the water is hitting a solid object (like the rocks in this photo).
In summary then:
-use the lowest ISO your camera has
- focus on manual (without ND on)
- use a good quality ND
- Use a small aperture (f13 – f22) if you want more in focus
- Look for solid objects to shoot against
These tools helped me work the magic:
