Long exposures can smooth out water, create an evocative mood, add depth and emotion to an image, intensify colors, and can force us to slow down and think about what we're creating.
When I think about this image, really I feel it. The stillness grabs me and pulls me into this image; I feel like I want to experience the calmness of this quiet blue morning. The promise of a new day is present in the hint of yellow and reds on the horizon, and the natural landscape points toward the sunrise, creating the desire to see what's over the horizon.
Here's how I start and what I think about when I arrive at a location and decide the best way to shoot it is by going slow.
I almost always have my camera set to Aperture Priority Mode and my exposure metering to Evaluative Metering Mode. I then set the Aperture to somewhere between f/11 and f/22, if you know you want to get the slowest shutter speed possible, then start at f/22. I then set my ISO to 50 or 100, attach a remote control/cable release ( or use the self-timer mode -- when I forget the cable release).
I start to think about the image, what I want to include, and start making a composition. I compose an image, then cover the viewfinder with tape, and take a test shot. This is just to set the exposure, and see if I need to add any more depth-of-field, see if the composition works etc. I then check the exposure and add or subtract light based on what the Histogram or Highlights Alert Mode tells me. I add or plus 1/3 a stop or more if the image is too dark, and I subtract or dial in minus 1/3 a stop or more is there's too much light. After I've made a test shot, I check the Exposure, Shutter Speed, and the effect and impact of the slow Shutter Speed image.
If the image isn't slow enough, I add a Polarizer or Variable Neutral Density Filter. I rotate the Polarizer around until the highlights on the water disappear, or the sky turns blue, or turn the Variable Neutral Density Filter around until the shutter speed is where I think it needs to be.
I take a second shot, and then evaluate the results: Did the water, wave, mist, etc. soften or slow down as much as I wanted? If not, and I used a Polarizer, I change to the Variable Neutral Density Filter. ( I use the Lee 4 x 4 Circular Polarizer here's a link to Amazon) If I used the Variable Neutral Density Filter, I turn it a little more. If it's turned one full stop, the exposure time will double. If I've done everything right, my second or third image will be the one I keep.
If the Variable Neutral Density Filter is too dark, switch to manual focus on your camera lens to get focused on the subject.
Use Aperture Priority mode up to about 30 minutes, after that switch everything to Manual Mode. Long exposures of over 30 minutes will take an Intervalometer and an extra portion of patience.
This was taken a little bit later in the morning as the sunrise had added an element of red into the sky and clouds. The water at 2 seconds isn't as blurred as the 5 seconds image or the first shot at 30 seconds. The 40mm lens flattens the depth of the image some and doesn't have the pull of the first image either. For me, this has more color, but less impact.
At half a second the fast moving water is blurred to a very soft, silky quality, but the leaves and vegetation surrounding the falls are also moving and thus a little bit blurry. ISO 200 was also needed as it was a rainy day. The Polarizer cut the reflection and highlights on the vegetation and increased the intensity of the color, besides helping slow the shutter speed.