The Gh2, although an excellent camera in many respects, has a few limitations when it comes to a classical orchestra. There are some serious aliasing issues with long strings such as double bass, harp, cello, and so on. Having said that, I like Flowmotion for say passaggi in the strings or tympani rolls. At its lowest setting, expect bitrates of say 32-35 for an Orchestra in Flowmotion under lights--you can get the concert on a 32gb. Hopefully. Orchestras classically blow out the highlights--sweaty, pale musicians, often with grey hair. So you will have some tough exposure choices. I consider it acceptable to overexpose the musical scores on wide shots but not on closeups. The GH2 does not have the dynamic range to cover the black to white of an orchestra under lights unless you totally nail the exposure. Would not go above 640 ISO. You will need more than one cam, and I recommend the Vixia HF G10 as a second cam instead of two GH2s. You will get realistic tone from the wood surfaces of the instruments and no stair-stepping on the strings, plus it has the extra dynamic range you need. Lastly, you will get the rock solid IS for any handheld shots or focus tracking you may want to do. Exposure tracking is very handy for orchestra work, and if there is no light on the face of the conductor you will need to push gain, which the GH2 won't do. The GH2, placed for a wide, full orchestra shot, will give you all that super, super sharp resolution which you will need for a full stage of complex objects--when paired with a 20mm or 45mm or Vivitar 55mm if you don't have one of the fancy primes. You will need a good prime lens. The conductor will be backlit, so figure that in if you need some vid of the front of the conductor. Ask for a "special" or bring a light. If it is a full size orchestra, and I mean full size, you may need to go with the 14mm from the 14-45, maybe with the contact taped over, or better yet the 12mm. Make sure your NR and contrast are dialed down all the way, and that sats are reasonable. If you have strong lighting, you will need to aim low on the expo, so don't dial the sats down all the way. I normally use five-six cams for orchestra, you can do it with two, but it will take some planning to get a convincing result. Three would be better, two rovers and a "safety". Orchestras are a top-down scene. If you look at a violin straight on, you see an edge. You will need some elevation to video the instruments and clear the music stands, which will be Manhassetts--fairly tall. Large reflective surfaces, such as a newer cellos or brass, can create a flashlight effect if moved slightly, so check all the lighting angles ahead of time.

Wow guys, this is impressive feedback! Thank you so much, @balazer, @DrDave, @Mark_the_Harp.

I will do some testing this weekend with Cake v2.0 vs. Flowmotion. The new Cake does sound great. A big improvement over the previous versions from what I could see in the sample video.

I will use three cameras - the two GH2s will be more or less my lock-down cameras. I'll also use a Canon for close-up work - a 60D (which I have used successfully in the past at this loaction) Luckily the intimate concert hall (Zipper Hall in Los Angeles http://s3.amazonaws.com/pa-spaces.production/attachments/950/Zipper%20Hall%20piano%20wide%20angle%203x5.slide.jpg?1300312961) is gorgeous, light-brown wood interior, the players are going to be all young (no problems with gray hair!) and the lighting is beautifully soft and even from above - no harsh or uneven spots on certain groups of players. It's a dream location. There is stadium seating and from the back of the (small) theater you get a nice elevated look of the entire orchestra. There are no harsh reflections on any instruments (thanks to the soft overhead lighting) and the only thing that's really blowing out is the conductor's score, but there is not much I can do about that.

I won't be able to walk around and I can't do super close-ups of single instruments and players. I only need some good general coverage with 3 angles to keep the editing interesting. I'd love to do a 5-6 camera shoot one day for the kind of projects @DrDave is talking about. My coverage is just one element for a short documentary and at the same time, it'll be a document for this orchestra.

The sound will be professionally recorded by the concert hall's technician. And I'll record pilot audio with all my cameras. And I am really looking forward to the new multicam feature in Final Cut Pro X. I love this app for sycing up audio with picture. Apple really had DSLR shooters in mind when they created it.

@DrDave - all great suggestions! Thank you so much again. I will see what the lighting person can do. I have actually shot video there in the past with my 60D. It looked pretty even. But the GH2's might be a bit different.

The recording engineer is giving me 2 uncompressed WAV files of both parts of the concert. Final Cut Pro X can sync them up automatically with my clips (and the on-board audio) and even creates new clips with the clean audio. It really works like magic. I have done that before. Quite remarkable. No matter how short or how long a clip is - FCP X finds it and puts it in the right place.

I"ll look into the G10. Excellent tip! Thanks again. I really have come to the right place here. Your suggestions have brought up some very good points. I'll try to put as many of them into action as possible!

I'll bring some matches...

And the bitrates for SpanMyBU v1 were around 70mbits/sec if I remember correctly, so you would be fine.

Good luck. Looks like a great hall! You mentioned blowing-out of the conductor's score, but if it's a big issue on the locked-off shots, you could probably correct that area a bit in post. Only other obvious thing really would apply to any artificial lighting - check that the you are not getting any weird strobing effects from the lighting. Shouldn't be an issue but one more thing to make sure of.

Great! That's the curse of classical music - the dreaded score. I love it when people don't use them!!

Excellent info, everyone. I really do appreciate all this great feedback!

@Bueller - you are absolutely right. But I did shoot a concert there already last fall. Only I didn't have my GH2 then - I was a Canon guy until early this year.

The good thing is, the orchestra is going to do a full rehearsal right before the actual concert - with the actual lighting and everything. I'll have 2 hours to get everything set up optimally. Without that luxury, I'd be very nervous, since you never know what your'e going to get... ;-)

If I can get them to wear their actual concert attire during the rehearsal, I could get some great close-ups that I couldn't get during the actual concert.

You can use cut ins from rehearsal that are real closeups, then you won't see that the music stands are not in the same place, and so on. Just make sure they have the same accessories. The thing is, it is a real pain to sync the audio with cut ins from a rehearsal. That's why I like the IS zoom for closeups.

I was directed to this thread because I had a similar question: I'll be shooting a theatrical performance, where many of the issues are the same. I've installed the Cake 2.0 patch, and I hope that'll work.

I did learn that, when the audio sample rates are set higher than 19200, the sound won't play back on the camera. Will it play back with an external HDMI monitor?

(And yes, I did try several searches to find previously-discussed answers to this question. Didn't work out.)

@edgenumbers, I'll give that a shot, too.

I just tried the Cake 2.0 patch, but under very loose conditions. Seems to work OK, but for some reason, my camera screen blanks out every so often. I haven't seen this happen before.