I have been approaching the same way I do stills. I shoot a short test then play back in camera and check the histogram there, I guess it's a bit long winded but I find the active histogram confusing. I would be interested to hear others thoughts on this.....

Basic question, so bear with me - when exposing using a grey card, is exposure correct when the histogram turns white?

Sure. That said, with the DR and low light noise/banding of a GH2, I often find it's better to shoot gray for reference and color correction but push the exposure as far as possible to the right on the histogram until just the smallest specular highlights are clipping.

It all depends on the shot, but the thing to remember is that you can expose the shot the way you need and bring the footage back into like in color correction. The gray card or color bars can also be a post-production tool.

That's a 1/2 stop -open- . (Drat, need even more light...)

I have a gray scale card with 20 steps. It has A mark on step 0 (100%), M mark on step 7 (65%), and B mark on step 16 (20%).

On GH2 with spot metering, M mark gave the most dynamic range. Set EV to 0 based on the M mark. Then EV reading on the skin was 1 1/3 which is my target.

For me the easiest, quickest (default) is to keep the GH2 on spot and hit whatever's about 18% grey in the shot I'm shooting, realizing of course that the spot follows the auto focus as well. So when using the touch screen- I touch for focus to frame and see the shot; then touch for exposure; then touch for focus again and then shoot. Focussing manually you can just touch your old spot metre all over the place and giggle.

But it's very subjective. Personally I don't find the histogram as helpful as I had hoped. It tells me what my eyes already can see in the LCD, which for me is pretty good for lighting but useless for focus. But if I was actually lighting a scene (and not just shooting what's in front of me) then I'd use an incident light metre.

But if I had to pull focus, well, I'd either pray, buy a monitor and all that, or hire a guy in a team as part of a crew that deserves to be paid as well as the catering truck that's required to feed 'em!

So I prefer the prayer option, obviously, knowing that if I was to ever screw up I can always run away and cry, believing that some kind of entity beyond the somewhere and when might love me anyways. Maybe

An 18& gray card and spot metering works pretty good too. I use it sometimes, but I find the best way to me is to use a light meter.

You can't do this on the GH2. The 'zebra' function isn't a traditional zebra, it simply flashes overexposed areas white. You can use the histogram and a 18% gray card to fill the screen and show the skin tone level.