If the subject is in front of a bright light this can also cause problems. Try moving, so that the light isn't directly behind your subject. You may be using too much flash. If you are using forced flash, switch to automatic, or switch it off. This may be caused by taking photos in artificial lighting conditions.
Picture quality is poor Try cleaning the camera's lens.
Use a lint-free cloth. Unexpected 'framing' At times what you see through an optical viewfinder isn't exactly what the lens is picking up. This is particularly likely to happen when taking close-up pictures. Many cameras have offset markings in the viewfinder to help. If there's a built-in screen, this will show you exactly what the picture will include.