Not working hands-free
A tripod is the best way to ensure sharp photos at very slow shutter speeds, but even the sturdiest set of legs may not prevent details from looking smudged if the camera isn’t perfectly stable. The action of pressing down on the shutter release button can jog the camera, so it’s worth triggering the shutter with a remote release, or using the self-timer or exposure-delay function for pictures that aren’t time-sensitive. Vibrations caused by the mirror moving (to expose the sensor to light) can also lead to soft shots. To remedy this, use the camera’s Mirror Up (MUP) mode or activate Live View, as the mirror is moved out of the way in Live View.