Photographs have the ability to not only show the world as it is – but also show the world as it would be if the eye was infinitely adaptable and controllable. After all, that is essentially what a camera is, an eye that the photographer can control in ways to capture the world in ways well beyond what any human eye can. From capturing the Milky Way in all of its detail and beauty, or freezing the exact moment a Great Blue Heron snatches a fish from the shallows, or capturing movement through long exposures allowing water and sky to soften and streak in beautiful patterns. It is the last that I want to take a moment to discuss, both the tools and techniques that I have found work well for bringing to life long exposure landscapes.
Being able to take long exposures requires having a bit of control over both your camera and the light coming in to it. Having some sort of manual or at least semi-manual control setting on the camera is a must. Depending on how fast the moving elements in the photo are moving you may need as little as a few seconds or as much as several minutes of exposure time to capture the moment. For instance, waterfalls and fast-moving streams get soft with some texture in a few seconds, lakes I often try for a minimum of 30 seconds to flatten out the water, and for clouds closer to a minute or more is usually required to get much in the way of moment effects that look like they were intentional.
The photo above is from the south end of Yellowstone National Park at Lewis Falls. I captured many photos of the falls from multiple angles and with different shutter speed lengths. This one was made by pairing my Tokina 11-16m lens stopped down to f/16 with the B+W 110W filter (10 stop) allowing for an exposure of just over 60 seconds in full daylight. In bright sun, 60 seconds is about as best you can hope for with a 10 stop filter in most cases. Stopping down beyond f/16 will further soften the photo due to diffraction of light coming in through the small aperture more than I care for. It is the dramatic different between the sharp non-moving elements in the photo (the trees, and rocks in the river) and the flowing water and moving clouds that add so much drama to the photo. Loss in detail and sharpness in what is supposed to be sharp greatly diminishes the look.
Speaking of sharpness and detail vs movement, here is a photo I took in the Grand Teton National Park in Wyoming a few days after the Lewis Falls photo. The first evening in Grand Teton I decided to scout my intended photo location for the next morning at the Mormon Row barns, planning to get the classic golden hour morning shot with the mountains all lit up by the rising sun with the barn in the foreground. The weather however had other ideas for me, as the cloud deck was rapidly descending even that evening, starting to obscure the high peaks of the mountains from view. What I did see was that the clouds were moving quickly over the peak due to the wind that was picking up. Wind can both be an ally and an enemy when capturing long exposure photos. Especially with cloud shots, wind is of course needed at least at the cloud’s elevation to move them to get the cloud blur. However wind at ground level will cause camera shake on anything but the most sturdy of tripods, ruining the sharpness of the foreground elements even if they themselves are not being effected by the wind. Add in any tall grass or trees in the near foreground of a long exposure shot and wind can certainly ruin the intended look. Luckily for me, the wind at the ground was not too strong and this five and a half minute exposure shot (yes over 330 seconds!) has good detail in the foreground in the barn with plenty of streaky clouds along the peaks of the mountains.
With wind being such a big factor in the success of most long exposure shots, finding the ideal location to set up the shot is 50% of the battle. In this shot of Stone Creek in Bridger Canyon near Bozeman, Montana I was able to find a location that was sheltered from the light breeze by the trees and higher ground on the right of frame. The air along the creek, while being rather cold due to the mountain run-off stream, was nearly perfectly still. The leaves of the bushes and trees in frame are nicely in focus and sharp while the creek flowed for the 72 second exposure time giving the water a soft silky appearance even as it flows around rocks. Again, even with the fairly shaded location, my 10-stop B+W ND filter as required to get this length of exposure time. Unless you plan to do all of your long exposure shots at dusk or in full darkness, a strong ND filter is going to be required along with a good tripod. I have both a 5-stop and 10-stop ND filter for my wide-angle lenses, the 5 stop is good for getting some flow out of waterfalls and other fast-moving water, but the 10-stop is pretty much a requirement to get more than a few seconds exposure time in full daylight.
One thing to note about high-stop ND filters is that they do come with their own difficulties and issues. The first issue is how to focus when less than 1% of light coming into the filter is making it into the camera. Looking through the view finder is nearly pitch black, and using the live view of the camera is almost as useless. In bright light I can sometimes see enough to get a general idea of the composition of the shot, but there is never enough detail to focus the lens. Therefore, it is more or less required that the camera be setup, the shot composed, lens focused, and then the filter be put into place. There are large square filter setups that allow you to slide the filter into a holder from above that is easier to work with in this situation than a screw-on filter like the B+W 110W that I have, but also costs yet than the already expensive B+W. Especially when handling the filter over (flowing and/or deep) water, or over rock, this becomes a nerve-wracking proposition. The other issue with very dark ND filters is that they are rarely truly neutral. That is, they do not actually block all light the same and thus create color casts to the resulting images. Some brands tend to cause blue tone casts, others brown/red hues. My B+W causes brown/reddish hue to most photos that mus be dealt with in post processing. While some long exposures look great as B&W photos, thus quickly eliminating any concern about the color cast, I often choose to keep the photo in color and use the excellent tools in Lightroom and other software packages to correct the color. Using Lightroom’s white-balance correction is sometimes enough – however the photo to the left of Hyalite Creek south of Bozeman required a more detailed solution. Getting the sky to the correct color balance caused the water in the foreground to become too blue, but getting the water correct kept the sky too warm. There are many was to go about correcting this situation, I could have chosen to simply using the adjustment brush in Lightroom to paint in additional white-balance correction in the sky and/or water areas. However in this case I decided to make two versions of the photo, export both into Gimp (a freeware alternative to PhotoShop) and then manually blend the two versions together to get the exact balance I was looking for. This is a fairly new technique for me, and one I am still learning to use, but I am quite pleased with the outcome in this case.
Learning to overcome the difficulties of using high-stop ND filters was one of the paths of exploration that I took during my September trip to Montana and Wyoming. I had only purchased the B+W 110W a few weeks previous to my trip and had only taken a few quick test photos before I left. But without it, I would have never been able to capture some of the unique and awe-inspiring views that I took in during the trip in the way that I wanted to. Waterfalls in full daylight would not have been smooth and silky, rivers would have been choppy and rough, and this photo of Lake Yellowstone would have just looked like a lake with some haze on the horizon. Instead, within the 20 seconds that the shutter remained open, the lake’s surface smoothed and the haze on the horizon gave even more depth to the mountains on the horizon.
I have thoroughly enjoyed starting to exposure the possibilities of long exposure photography, and plan to find interesting opportunities for capturing both movement and using movement to create interesting looks to my photos in the future. I hope these examples have been able to give a glimpse of what is possible with the long exposure technique and perhaps inspired any photographers reading to explore the possibilities themselves.