Really are many issues to consider.
Among other issues, we have no public, will be recording to a DVD SHOW, I think it would be interesting to illuminate the background (trees), the soloist and the conductor will be lit separately, I believe that putting cameras in the middle of the orchestra is not really a good idea for cause the amount of musicians, the musical style is modern.
Initially I had thought about using a light flat, single-source attack with a powerful, single (HMI), diffuse, and compensate her. Simple as that.
All musicians will be dressed in white in nature, so I think the more the light is simply keeping with the naturalness of the picture.
Regarding the use of sources, I am not safe with respect to their choice (HMI).
Have to look on the Sony Z1, I do not know its limitations, this information from ISO is very important to me.
I still thank the help of colleagues.