This belongs in the beginners questions really and will probably be closed by VK pretty soon...
Shoot at white card - decent photography card is good enough - then set balance to it. If you have no white card find the closest thing to natural white and setup WB from there - manually. Its fairly important to neutralise the whites and grays as I find it helps in the grade and saves a bit of time. However, there is no golden rule to WB as some people use WB to give a 'look' to their exposure, all things intentional.
A good video from mpgxsvcd covers all the basics for you.
In an attempt to save this condemned thread....in a specialized store i saw that they sell "digi grey", for 16 or 25€ (with casing and a somethingpod). Apparently it's supposed to help with the white balance (for those who don't know, it's a grey card with a white and a black patch, and some basic colors too, you can point the camera at it to make the white balance).
Is it really useful ? (like is it worth it spending the money on it ? ) or more of a scam ?
Make sure you shoot the WB card several times during the session and you can balance it in post, if needed. Adobe Premiere CS6 also gives you the option to shoot an entire color chart, and use the whole chart in post. You can also create a custom WB, but you still need actual footage of the card taken a several intervals and angles.
@driftwood Does manual WB work in practice? I was out to south of Spain and my summary to WB was: manual WB with a piece of white paper came up too yellow / greenish. Daylight WB was too blue. Auto WB had some variation but over all it looked best and variation were not too heavy so thar they could be corrected in post.
I will check one of the grey cards also during next days
Honestly, I've been doing videography creatively and professionally for several years and have never found it necessary to use a white card. I have a pretty good intuition for when colors look right, and most of the time just rely on that. In particularly tricky lighting situations, I base my WB setting on something white that's already in the scene, or on making skin-tones look natural (top priority, anyway).
One thing that I would say about WB on the GH2, though, is that because it tends to shift toward green, more so at higher ISOs, I always dial in a custom color tint. To do that, press the down arrow from the WB menu. This'll bring up a grid. At low ISOs I usually do 2 clicks down (toward M-) and 1 click to the right (toward B). At higher ISOs I go as far as 5 clicks down and 3 clicks to the right. Really helps control the greens.
I've heard and read that the red channel on the GH2 introduces unwanted noise in the image. Saw it from that guy DrewNetwork. He recommends always shooting in 3200 and correcting in post to get rid of this problem. Possibly even boosting the in other WB modes. I've started this practice and it seems to work really well with the introduction of red in CC. Have you heard of this, tried it or just think it's crap? The tests he's done seem to be pretty accurate and it doesn't take that much of a shift to even everything out, something I was worried about.
@vicharris I watched that video from DrewNetwork while waiting for my GH2 to ship, but never got around to testing it afterward. I haven't had any real issues with excessive noise, but I also haven't shot much high-ISO material. I'll try this out today and post my thoughts.
@vicharris That's a cheapo matte box from FilmCity, bought on eBay. It's about as bare-bones as matte boxes come. I'm planning to sell it soon and buy a swing-away unit with rotating filters.
The idea of an automatic colour correct using a Macbeth chart caught my imagination and a quick bit of googling found this £50 plugin for AE 5/5.5. I haven't tried this yet, but I'm definitely going to give it a go.
EDIT Here's the link: http://www.mattroberts.org/MBR_Color_Corrector/
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