Is there a way to get DC power to an EVF without an Anton Bauer-type battery? If there were a way to tap power directly from the camera that would be ideal, but it doesn't appear to be possible. I have looked for something that goes in between the battery and the camera to siphon power, but I don't think anyone makes one. I have heard of NP-F970-style batteries with a tap on the back, but I can't find them anywhere.

The idea is simply to have one battery/battery type and one charger type for a lightweight rig and less anxiety in tiny-crew ENG shooting situations. Any similar solutions out there?

The NP-F style battery with tap on the back that I use is the Swit S-8972. I use it to power my camera and nanoflash.

S-8972 DV Battery with DC Output for Sony NP-F970/770 (http://www.swit.us/s8972-dv-liion-bat8972.html)

Thanks Cees. These are priced the same as retail NP-F970s, so it's not a bad option at all.

In the product description it says that it has an LED battery level indicator. Can I assume this implies that it does not supply InfoLithium data to the camera?

On my FS700 it does supply information to the camera. However it is not as accurate as with original batteries. It remains on 100% for quite a while and then goes down a bit faster. It gives a reasonable indication however.

Surely it doesn't actually supply 'information' to the camera in the same sense as a genuine Sony Infolithium as it doesn't have the datalink. More likely that the camera senses the voltage coming in which holds up until just before the end-point drop.

Cees, as long as it doesn't catch me off guard I think it would be fine. How much time is typically left when the camera starts to drop percentage?

I think that when the battery is still around 75% full the indication in camera starts to go down from 100%. Then I think the battery goes dead when the indication on the camera is somewhere between 10-30%. I haven't checked that properly, I useally switch batteries, when the indiaction reaches around 30%. So I never get surprised.

The led indication on the batteries does not really help you much more. It goes from four leds down to zero leds indicating the status of the battery, but each of my battery is still about half full when the leds give no indication any more. So I trust on the indication in the camera. And since there is an indication going down from 100% to at least 30% I have a reasonable indication that it will not suddenly die unexpected.