Capturing an excellent long exposure photograph is not as simple as setting your camera to a slow shutter speed and firing. Any adjustment to shutter speed will require you to make further adjustments to other exposure settings to avoid overexposing your image, something that can still occur even in complete darkness. Taking long exposure photos requires patience, alongside simple trial and error.
Firstly, set your ISO as low as possible to reduce the sensor’s sensitivity to light. Next, select a small aperture to limit the amount of light captured by your camera’s lens while increasing your field depth. This can often be tricky to balance shooting long exposures during the day without using additional equipment like a tripod.