Can anyone tell me if having the phantom power switch "on" and a mic attached, drains power from the camera battery even when the camera is switched off.
Thank you.

No, don't worry about it.

Bill

Anybody knows how much more a phantom-powered mic sucks from the battery than a battery-powered?

That will depend on the microphone in question.

The typical phantom power current rating for common video shotgun mics like the AT837 or Rode NTG-1/2 is on the order of 2-to-4 mA. Assuming 70% conversion efficiency and a 7 volt to 48 volt up conversion in the camcorder, that would translate to something on the order of 20-to-40 mA of battery current used to power the mic. The nominal camcorder load is 1000 mA.

So in practical terms...?

A battery powered mic required no current from the battery if phantom power switch is off. In practical terms I would estimate very roughly 3% less run-time from from the camcorder battery when using phantom power with a mic. If the BP950 gives you 200 minutes of runtime without phantom power, expect on the order of 194 minutes with phantom power turned on for one mic. But your mileage will vary depending on the particulars of your mic.

Thanks, exactly the kind of information I sought.

Hi there

There are two main reasons I always run the mic off the cameras phantom power.
1) the mic can't die and leave you soundless..ie the battery dies without warning... happened twice when I used an FX1..
2) the mic is lighter without a battery fitted...

On my Z1 I have noticed no real world difference with the mic powered by the camera...

cheers
Gareth

A third potential reason is that many mics have somewhat better characteristics when on phantom power; i.e., lower output impedance and tolerate higher sound levels before objectionable distortion. How much benefit depends on the particulars of the mic in question.