When taking portraits, a good shutter speed would be 1/200. This speed is ideal as it prevents the chances of having blurred images. Simply put, a fast shutter speed is ideal for portraits. If, for example, you need no flash as you are taking portraits in a well-lit room (daytime), a 1/200 shutter speed would be fine. This is great for handheld shots. For a tripod, though, use a 1/15 shutter speed.