Set the camera on a tripod in front of something that moves across your view. Make a series of exposures, from the fastest shutter speed on your camera to a very slow one. Adjust the aperture each time, or have the camera set so that it automatically adjusts the aperture so that the exposure stays the same.Take note of the shutter speed used for each frame. Compare the finished images. Find the slowest shutter speed at which the movement is sharply frozen. Make notes about each print in your learning log.
For this exercise I headed down to the Seymour River and set up my tripod on the river bank. The Seymour River is a fairly fast flowing river at this time of the year as we have had quite a bit of rain recently. Because I’m rather rubbish at shutter speed settings, I decided to try this exercise using my shutter speed priority and set the camera to auto ISO. I started out at 1/1600 of a second, with ISO 500 and aperture f4.5 at 92mm. I took a photo at 1/3 of a stop intervals (only 12 photos are shown here), stopping down to 1/5 of a second before my highlights were totally blown out. I noticed that the water is sharp until 1/200 – the splashes over the rocks still show definition and volume. However, one can also see at 1/200 that where the water is more free flowing (not splashing over rocks), it is beginning to smooth out. At 1/50 the droplets have consolidated and one can see the beginning of the milky effect on the “mini rapids”. At 1/25 the undulations of the water over the rocks are beginning to form. It is almost as if the water is “solidifying”. At 1/13 the undulations are move evident and the colour of the rocks and the water have begun to merge/streak together. The “mini rapids” are now beginning to look like candy floss in the water. At 1/10 there is sufficient motion blur in the water for creativity to emphasis the strong flow of the water, but still enough ‘realism’ that were one to crop a portion of the river, it would still be recognizable as water. I think this is my favourite photo. By the time the shutter speed is reduced to 1/5 the water has a painterly effect and is almost totally smoothed out and the rocks below the surface have totally lost all definition.
This exercise was definitely harder than I thought it would be. I found the tripod rather restrictive. I first attempted it with people walking across the viewfinder, but I had little success focusing on the moving targets. However, I’m determined to try this again with human subjects, so I will come back to this exercise again.