What Really Is the Difference Between These Two Types of Digital Images? The short answer is time. Although we are not talking about how long the shutter is open or shutter lag, those are considerations. In the process of taking a snapshot, you see something you want a photo of, you bring your camera up and take the photo. Very little, if any, thought goes into setting up the shot. In a great shot, you run through in your mind this list of ten things to consider before pressing the shutter button: