Answer:
Some cameras have something called “shutter lag” which is the time it takes from the instant the shutter is pressed, until the instant the picture is taken. This can be very disruptive to the photographer, and although it is not possible to eliminate this delay, it is possible to minimize it a lot.
Explanation:
One of the main causes of shutter lag in dSLR cameras is the mirror that allows you to preview the image, since it needs to be raised in order for the light to reach the sensor. This time is minimal, however, and varies from camera to camera.
The focus delay exists in professional cameras as well and needs to be avoided in the same way, but the time it takes for the lens to clear the image, in these cases, is slightly less. Another factor that contributes to the photographer is the use of manual focus, completely eliminating this type of shutter lag.
Another type of delay that occurs is the image processing time by the sensor. This is not really a shutter lag, since it occurs after the photo was taken, but it can hinder the capture of sequential photos, as many cameras spend several seconds processing the same image.
