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We have a lecture hall (diagram below) that holds about 200 attendees. The speaker stands or sits on an elevated platform in the middle of the room and the attendees make a semi-circle around him. We recently added an option for attendees to connect to the lecture remotely using GoToMeeting. To do this, we added a laptop (2) to the room and ran wires to the sound box (1). We have a simple webcam on a stand beside the speaker (3). The problem is, we get a really bad angle on the speaker with this setup!

We want a new solution where we'll be able to see the entire speaker's platform on the video. This will allow the speaker to move around without going off screen. We also want a straight shot at him. I thought we could put a camera in the back of the room (6) and connect it to the laptop with a long cable.

  1. Would a traditional USB webcam get a clear picture of the speaker at that distance? (It's about 30 feet from the speaker's platform to the back)
  2. Could I use some kind of zoom lens to compensate for the distance? Would that distort the picture?
  3. Is there a better place to put the camera to accomplish this goal?

Lecture Hall Diagram

  1. The sound box. Has the mixer, amplifier, wireless mic receiver, etc
  2. Laptop running GoToMeeting.
  3. Stand on the speakers platform with a monitor and webcam for the remote attendees.
  4. The internet connection
  5. The wirelss mic
  6. Suggested new camera position
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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:

enter image description here

For this set, you will need:

  1. Camcorder as previously discussed
  2. Tripod that moves nicely
  3. HDMI to USB converter as previously discussed
  4. HDMI and USB wires
  5. 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:

enter image description here

For this set you will need much more:

  1. 3 Camcorders as previously discussed
  2. 3 Tripod that moves nicely
  3. 3 HDMI to USB converters as previously discussed
  4. HDMI and USB wires
  5. HDMI extenders. There's several varieties, discussion of which is too much for this answer.
  6. Video mixer, some of which are discussed in the resource link.
  7. At least 4 techs managing mostly the cameras:
    1. One for each camera
    2. 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.

Source

I work for a company that does this all the time. If you need professional help with content production you can find information in my profile.

  • Thanks for such a thorough answer! What's the advantage to using an HDMI to USB converter instead of pluggin the camera's USB directly in to the computer? – just.another.programmer Jun 7 '16 at 6:41
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    @just.another.programmer For me, familiarity with a proven method. If you find a camcorder that claims to stream the video over usb, then feel free to try it. It probably will work, but I would personally check that it will work with whatever software you plan on using (Gotomeeting). – user24601 Jun 7 '16 at 16:34
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HD TV is almost a 2:1 aspect ratio. You want about 3' of vertical (mid-chest to above head) and thus almost 6' of horizontal field of view (f.o.v.). To get 6' fov at 30' you need about an 11 degree field of view. Which is like a 200mm lens in 35mm photography or a 100mm lens for m43. For tiny, 1/3 inch sensors, you need a 25mm lens.

  • Could you explain the math you used to calculate these numbers? – just.another.programmer Jun 7 '16 at 6:35
  • The first part of the math is basic trigonometry: one can calculate an angle knowing an altitude (distance to the subject) and the base (one half the width of the subject) of a right triangle. The hypotenuse is the square root of the sum of the squares of the altitude and the base (Pythagorian Theorem). The sin of the angle is the opposite (base) over the hypotenuse, so the angle is the arcsin of the opposite over the hypotenuse. – Michael Tiemann Jun 8 '16 at 2:12
  • The second part of the math is using a resource that tells you field of view for a given lens using a given image format. If a given lens has a 46 degree field of view and you calculate you need an 11 degree field of view, then you need a lens that's approximately 4x the focal length of the given lens. – Michael Tiemann Jun 8 '16 at 2:13

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