1 Use a tripod
When shooting any long exposure, it’s best to use some kind of support, and for very long exposures a sturdy tripod is essential. Set up your tripod making sure the feet can’t slip to avoid any kind of movement. You’ll also need a remote release to avoid touching the camera when releasing the shutter in Bulb mode. If using a weaker ND or a polariser then attach this now, but if you’re using an extreme ND then hold fire.
2. Compose the shot
Turn on LiveView and cover the viewfinder using the eyepiece cover or your hand, before composing your shot using the LCD screen. This will avoid light leaks through the viewfinder, which can create dull spots on your image. Mirrorless users won’t need to do this. Find your composition and lock off the tripod. Now activate the virtual horizon to make sure the camera is level and you’re all set.
3 Select settings
Set the camera to aperture-priority mode and choose an mid-to-narrow aperture at ISO 100. If you’re not using an extreme ND then you can now shoot away using aperture-priority mode. For extreme ND users, take a test shot, apply exposure compensation if necessary, and make a note of the exposure settings. Transfer these over into manual mode, but set the shutter speed to Bulb.
4 Manually focus
Switch your lens to manual focus and turn on LiveView. Zoom into the waterfall itself using the magnify controls on the back of the camera. Now rotate the focusing ring on the lens until the image looks sharp on the LCD screen. With a waterfall that’s close to the camera with nothing behind it, this method works perfectly. Now turn off LiveView and attach your extreme ND filter.
5. Calculate exposure
My test shot was at 1/8sec. Shutter speed simply doubles for each stop, so for ten stops I counted 1/4sec, 1/2sec, one second, two seconds, four seconds, eight seconds, 15 seconds, 30 seconds, one minute, two minutes. Two minutes was the perfect exposure. Use a watch or phone as a timer, and release the shutter with a remote, locking the shutter open for the duration.