then why camcorders?
How is the streaming going to happen.
Good low light behavior means wide lens diameter (70mm or larger) and big imaging chips (1/3" or larger, 3CCD r 3CMOS preferred.
The camcorders you post are basically consumer - perhaps prosumer grade - that are designed to record/capture video. Studio camera do not have a recording capability... they connect to a "control room" that has switchers. monitors, recording and the interface to where ever the transmission is going to (in this case, apparently, the internet). There is also an audio control system. The studio cameras might have a mic mounted to them, but the talent will usually have mics mounted to them.
Sony, Canon, Panasonic and Ikegami (among others) have "studio" cameras available
http://pro.sony.com/bbsc/ssr/cat-broadcastcameras/cat-hdstudio/
http://pro.sony.com/bbsc/ssr/cat-broadcastcameras/cat-broadcastcamerapantiltzoom/
(these remote cams will also need a PTZ controller)
http://www.usa.canon.com/cusa/professional/products/professional_cameras/ptz_cameras
http://www.panasonic.com/business/provideo/professional-camera-systems.asp
http://www.ikegami.com/product_indexb.html
Using camcorders not designed to do what you want will lead to frustration and create a series of items for your to "work around" that you don't need.
I also suggest you find/hire a consultant to design your implementation.
I would not use any that you have listed for the conditions you have described. If we can only choose from camcorders, then the starting point will be Sony HDR-FX1000, Canon XF300, and similarly priced equipment from Panasonic or JVC...
We are trying to built a video-system for streaming over the Internet. After digging some more on the Internet we narrowed it down to these three options:
- Sony HVR-HD1000U, entry-level professional camcorder with HD capability, currently fading-out
- Panasonic HC-X920, remarkable sensor specifications (1/2.3" 3 backlit sensors, min. lux performance)
- Cannon Vixia HF G20, top of the line in online reviews, smaller sensor than Panasonic's
We are looking for a primary camera that would be filming from the back - 40-50m away from the scene - in low/difficult light setup. What would you choose and why? We're also open to new ideas.

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