This photo of Wineglass Bay on Tasmania’s Freycinet Peninsula was taken using an extremely slow shutter-speed of 80 seconds. With most cameras you won’t be able to keep the shutter open for 80 seconds without a) ending up with stacks of motion blur and b) ending up with a completely white image (because too much light reached the sensor). In fact in broad daylight shooting at ISO100 and a normal 35mm (or digital equivalent) camera, you probably won’t be able to keep the shutter open for more than about 1/10th of a second without ending up with some serious overexposure issues; most of the time in sunlight I’m shooting at 1/250 and f/8, or thereabouts.
The joy of long exposure is the way in which moving elements either disappear (they don’t stay long enough in one place for the light they reflect to register on the sensor) or, if repetitive or slow moving, become blurred. Here, while the beach and the mountains behind are static and remain relatively sharp (sadly the gusting wind meant that a little fuzziness crept in to the frame), you can see that the clouds have streaked into long wispy things, and the sea has mellowed out into a soupy azure mist.
I get this effect (one which I’m very fond of but don’t generally have much time to invest in or perfect, hence the scarcity- and frequently, paucity- of images in this style in my portfolio) by using a Neutral Density filter. ND filters, as I’ve discussed elsewhere, are effectively colourless grey (hence ‘neutral’) gels of varying darkness that fit in front of the lens. They come in a range of values, the most common being ND2, ND4, ND8, ND50 and ND400. The numbers relate to the darkening factor- an ND2 halves the amount of light as would normally enter the lens, an ND8 lets in 1/8th as much light, and so forth.
The above shot was taken with my favourite and oh-so-subtle ND400. I’ve always figured if you’re going to go for an effect, you might as well go the whole hog. That basically means that just 1 in 400 photons that would normally reach my filterless sensor can get through the gel, or in other words, the image is 400 times darker- and the shutter needs to be open 400 times longer than in normal conditions to get the same exposure value. To add to the effect, I’ve shot at f/22 (the smallest aperture) and stacked the ND with the polarizer to get more colour, and to stretch out my time window as long as possible to magnify the blurring effect. It goes without saying that I had to trek my tripod onto the beach to get this image.
I’m moderately pleased with the output here. The colours are great, though the frame was slightly overexposed, and as mentioned above the gusting wind knocked the tripod about a bit so I didn’t end up with as crisp an image as I might have liked (click the photo to see it larger). I do truly love the effect, although shooting such a calm waterfront on such a wide-angled lens meant that the relatively gentle waves washing on shore didn’t make for as dramatic an image as a rougher sea would have done, where large portions of the beach would have been turned to mist.
Landscape photographers with a penchant for water features make use of the ND filters a lot, though generally the lighter filters (ND8, for example) which allow for just a second or two of exposure, giving the water that lovely milky texture you find on some of those wall-prints that people who actually get paid for their photography tend to produce (should I be learning something here?). I really want to take more time and apply the neutral density technique more widely. Unfortunately once you find an appropriate subject in the right light, it then takes time to set up the tripod, prefocus, set the camera up for long-exposure (turn off Auto-focus and Image Stabilization), get the polarizer set up, then add the ND filter (without altering the polarizer-because once the ND is on you can’t see anything through the lens- it’s too dark), plug in the cable-release, and so-forth. It takes a couple of minutes to re-set for each shot, and in changing light you don’t get much leeway for making mistakes- especially when you really have to guesstimate the amount of time to leave the shutter open (with the ND400 stacked with a polarizer at f/22, usually between 45 and 90 seconds, depending on the light).
That’s a lot of talk about what is a pretty niche little application of some fairly uncommon photographic gear. For those of you who have read this far- congratulations! I appreciate your commitment. For the rest of you, I hope you liked the photo at the top of this post before you got bored. To reward you, here’s another shot- the same vantage, but this time shot with a 1-second exposure (by opening up the aperture to let more light in) rather than 80 seconds.