Slow shutter
speed combined with panning the camera can achieve a motion blur
for moving objects. In photography, shutter speed or exposure time is the length of time a
camera's shutter is
open when taking a photograph. The amount of light that reaches the film or
image sensor is proportional to the exposure time.
Here is an
example of shutter speed, as you can see by the photo the bigger the number the
more it catches the movement in one photograph.
Aperture
In optics, an aperture is
a hole or an opening through which light travels. More specifically, the aperture of an optical systemis the opening that controls the cone angle of a package of rays that come to a focus in the image.
Diagram of decreasing
aperture sizes (increasing f-numbers) for "full
stop" increments (factor of two aperture area per stop). In optics, the f-number (sometimes called focal ratio, f-ratio, f-stop, or relative aperture) of an optical system is the ratio of the lens's focal length to the diameter of the entrance pupil. It is a dimensionless number that is a quantitative measure of lens speed, and an important concept in photography.
Aperture examples:
Aperture examples: