Night photography is a challenging hobby. You are taking a picture in conditions where you can barely see your camera. You have to wait around in the coldest part of the day for long periods of time and all those minutes could be wasted if you don’t plan to overcome the basic obstacles which shooting in the dark can present.
Exposure is a critical element in photography. Until the emergence of Digital photography, it was common practice for landscape photographers to slightly underexpose a photo for better highlight detail and increased saturation.
HDR means High Dynamic Range photography. It refers to a method of capturing a larger range of light detail than is possible with a single exposure.