You're on the right track. Your set looks okay to me and that's probably what I would do. But, no, there is no webcam I've ever seen that would be a good fit for this. You need a proper camera and possibly some additional hardware and software to assist in the upstream process.
I believe you can best accomplish what you want with a consumer grade camera. There are plenty of consumer grade camcorders that also have an optical zoom at 10x or higher, and they are fairly cheap too (I assume budget/time is tight, hence the webcam/gotomeeting solution). I would get something with at least 10x optical zoom. Completely ignore digital zoom specs and if you can, turn it off in whatever camcorder you get.
It seems there are camcorders out now that can send the video signal over USB, for exactly this purpose. I've never use that, however, and it may not work that well with Gotomeeting. I would use a camcorder with an HDMI out, then incorporate an HDMI to USB hardware option, which should be able to connect to Gotomeeting as if it were a webcam. There's several hardware recommendation found here.
You will also need to change to location of some of your set. First, I would move the sound box and the laptop running GoToMeeting to the back with the camera (item six on your diagram). Whenever possible, always put all tech in the same location: "The tech table". The primary reason is the ease for your techs to manage the equipment. The secondary reason is the lines. USB and HDMI can't run very far without additional hardware, also longer runs means more work, more expense, more risk, etc.
Here's your new diagram:
For this set, you will need:
- Camcorder as previously discussed
- Tripod that moves nicely
- HDMI to USB converter as previously discussed
- HDMI and USB wires
- At least one tech managing mostly the camera, plus the other hardware.
If budget and time are not big factors here, I would consider adding one or two more cameras, possibly reposition the original camera, and add a video mixer. In this kind of audience set, called "arena", a dynamic speaker will tend to turn frequently and rapidly to address and engage all the attendees. This means he will be facing your camera less than half the time, which makes for a boring and unengaging shot for your remote attendees. Adding one or two more cameras would significantly increase your set complexity and cost, however, it would add a level of professionalism that is worth it if you have the budget, time, and space. Consider this resource that discusses specifically using multiple cameras for Gotomeeting.
Here is a diagram for that, where 7 and 8 are cameras and 9 is a video mixer:
For this set you will need much more:
- 3 Camcorders as previously discussed
- 3 Tripod that moves nicely
- 3 HDMI to USB converters as previously discussed
- HDMI and USB wires
- HDMI extenders. There's several varieties, discussion of which is too much for this answer.
- Video mixer, some of which are discussed in the resource link.
- At least 4 techs managing mostly the cameras:
- One for each camera
- One managing the video mixer
It total, I would say this set would cost 5 to ten times more than the first set, most of that being labor.
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