Well I have covered this before and I am sure I have explained this to you on a previous post. Sometimes the phone will change which lens it is using when zooming in and out depending upon how close you are to the subject, lighting, camera mode you are in etc. The phone literally swaps which camera it is using so there will be a shift as one camera gets turned off and another turned on, they are in different positions on the back of the phone so I don't know what you are expecting exactly? But when the phone only uses the one camera it zooms perfectly zoom.
TechZilla - Samsung Members Star