Something weird seems to be going on with my picture file numbers. Not long ago I noticed that the file numbers were something like IMG_61XX. I thought this seemed off from what it had been. When I checked previous files, they were in the range of IMG_19XX. Its like my camera has added about 4000 to my previous file numbering. I don't think I changed any settings to cause this to happen. Does anyone have any idea what could be going on?