I have a DX6340, and am finding it to have poor dof qualities. I can get a blurry background only if the subject is close to me. If I am 5 feet or more from the subject, the background is not blurry (I want it to be blurry). Changing aperature doesn't have any effect on this either. Is this a poor quality of the camera? Also, the aperature can only go to a 5.6 unless I have it zoomed out as far as possible, then it will offer anywhere from 8.0 to 13.0. Is this common?