See that shadow in the bottom/middle of the above image? You may have seen this happen before if you're using an on-board flash. It happens when you're shooting with the on-board flash and a wide angle lens. The smaller and shorter flash on the camera just doesn't have the range to clear the lens, which creates a shadow.

(It may also happen if you're using a hood. In this case, remove the hood to remove the problem).
Fixes include zooming in, or using an external flash (recommended) that fits either on your cameras hot shoe or on a flash bracket.