Long exposure refers to taking a photograph with shutter speeds of between a few seconds to a few hours and is a great technique to capture striking landscape photos.
First, you will need to secure your camera on a tripod. Hand holding a camera with a shutter speed of even 1 second will produce a blurred image. Set your ISO depending on the scene and use Shutter Priority (Tv) mode to adjust your shutter speed up to 30 seconds. Using a remote shutter release, like Remote Controller RC-6, RS-60E3 Remote Switch or Canon BR-E1 Wireless Remote Control., alternatively the 2-second timer will avoid any camera shake as you press the shutter.
As you can see with the above example, the movement of the Earth during the long exposure has created this star trail effect across the night sky.
The challenge shooting long exposures during the day is setting the shutter speed to allow enough movement to occur. Ideally you want shutter speeds of more than a few seconds, so remember to keep your ISO low and aperture small. It also helps to shoot in overcast or shady conditions or at either end of the day when the light is dimmer. Alternatively invest in a filter that fixes on the end of your lens and prevents some light from entering. A neutral density (ND) filter will work best. Some compact cameras, like PowerShot G7 X series have an in-built ND filter that you can switch on and off in the menu.
With a low ISO of 100 and small aperture of f/16, shutter speeds of 1/10 and 30 seconds were used to capture the blur of the tide pulling in and out.