help with shutter speed

• exposure time of 0.8 Seconds.

• 1/4000 s: The fastest speed available in most SLR cameras. Used to take sharp photographs of fast subjects, such as athletes or vehicles, under good lighting conditions and with an ISO setting of up to 800.
• 1/2000 s and 1/1000 s: Used to take sharp photographs of moderately fast subjects under normal lighting conditions.
• 1/500 s and 1/250 s: Used to take sharp photographs of people in motion in everyday situations. 1/250 s is the fastest speed useful for panning; it also allows for a smaller aperture (up to f/11) in motion shots, and hence for a greater depth of field.
• 1/125 s: This speed, and slower ones, are no longer useful for freezing motion. 1/125 s is used to obtain greater depth of field and overall sharpness in landscape photography, and is also often used for panning shots.

• 1/60 s: Used for panning shots, for images taken under dim lighting conditions, and for available light portraits.
• 1/30 s: Used for panning subjects moving slower than 30 miles per hour and for available-light photography. Images taken at this and slower speeds normally require a tripod or other camera support to be sharp.
• 1/15 s and 1/8 s: This and slower speeds are useful for photographs other than panning shots where motion blur is employed for deliberate effect, or for taking sharp photographs of immobile subjects under bad lighting conditions with a tripod-supported camera.
• 1/4 s, 1/2 s and 1 s: Also mainly used for motion blur effects and/or low-light photography, but only practical with a tripod-supported camera.
• B (bulb) (1 minute to several hours): Used with a mechanically fixed camera in astrophotography and for certain special effects.