Voltage regulator draw at no load

I'm building a video trail cam with an unused VCR camcorder. I have the motion detector (peizo removal tread a week ago) and timing circuit compleat. I was planning on getting 6 volts from a 12 volt car battery with a LM350k regulator. When the camera is off, the total draw is less than 30 mA. The camera draws 1.8 amps according to the wall adapter. I could use a 6 volt battery but these are not so easy to come by cheap and the original camcorder battery is shot. Will there be wasted power or heat at the low current draw. Is there a better way to get 6 volts. Your thoughts and advice are appreciated.

I don't see why you shouldn't be able to use a 6V sealed lead acid battery.

You should use 3A fuse or PTC resistor (poly switch/fuse) to protect against a short circuit.