The new picture will have 'BARS' of two different pictures - the new one and the old one. I think this is a tracking problem with the recorders, and the old signal is not being erased, and the new signal is recorded just slightly to the side of the old one. If you don't have one you will have to have a special docking station to feed the video to the computer, or another camera. Buy at least 3 batteries and have them charged at all time. You will find if you are out shooting all day, one battery will not last the day.
Some cameras come with universal DC voltage in connections.
Those that do will allow you to use a motorcycle battery, and adapter. This will allow you to shoot for long hours with no worry of running out of power. A diaper bag makes one of the best camera bags. They are waterproof, have a lot of pockets, and are large enough to hold all your gear. Always carry your power supply, an extension cord with you and a two-prong adapter for your cord.