About Shutter Speed:
* Aperture, Shutter Speed, and ISO create your exposure.
* Shutter Speed is the time that the aperture is opened to let light in to the camera.
* A fast shutter speed will allow you to "freeze" images in action.
* A fast shutter speed lets less light in.
* A slow shutter speed "prints" the action and may create blur.
* A slow shutter speed can create interesting images such as light writing, star trails, etc. You must use a tripod for these effects.
* For portraits, use a shutter speed no slower than 1/100th of a second.
* For action shots, use a shutter speed no slower than 1/250th of a second.
* For light writing: ISO 100, 22 aperture, and 30" shutter speed.