A:Answer The smart aleck answer is, hit the shutter. The serious answer is, why did you choose the AP mode. Shutter preferred means the camera "chooses" the shutter speed you specified and adjusts the aperture to get a correctly exposed picture. Used often to reduce blur on action shots of fast moving subjects. Aperture preferred is often used where the depth of field is important (like portraits in particular). You set the aperture, two extreme examples, as wide open and that radically reduces depth of field to a shallow plane and if that shallow sharp focus plane includes a subject face it will be in focus but objects in front or back of the plane will tend to be out of focus. If you want everything in the picture "sharp" with AP, subject motion cannot be an issue. But set the aperture as "closed" or "small opening" and it will cause the camera to reduce shutter speed relatively to get a correct exposure, like a scenic with foreground objects and a background some distance away where you want BOTH in sharp focus, and motion isn't an issue.
