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Choosing Cameras and Lighting for Single-Speaker Webinars

Are pro video cameras overkill for single-speaker webinars? What's the best type of camera these ever-more popular productions, and what kind and how much lighting do you need to pull them off? We set up some common scenarios, ran some tests, and here's what we found out.

Consumer vs. Prosumer Camcorder

Well, this is kind of a strange one. When preparing for the webinar, I looked at the Panasonic’s image and felt it was about the same as the Vixia, though the Vixia’s white balance was obviously off. Looking at the two videos now (Figure 7, below), the Panasonic seems noticeably better overall, with superior overall contrast and detail. Part of that is because I set the Panasonic’s exposure manually, while relying on backlight compensation for the Vixia. But part of it is also the superior optics and imaging in the Panasonic.

Figure 7. Vixia (left) vs. HMC150 (right). Click the image to see it at full size.

Balanced against the slight increase in quality is the dramatic increase in difficulty of use, particularly for selfie webinars. Setting exposure manually when you’re the only person in the room is time-consuming and frustrating, though many modern camcorders come with WiFi controls that let you log in and adjust these settings from your desk. If you’re using one of those, it’s a different story.

On the other hand, would any webinar viewers notice the difference on their computer, notebook or tablet screens? I’d have to say probably not.

How Important is Lighting? Very

Again, I tested the devices under two conditions: optimal, where I deployed four softboxes, two on me as dual key lights, two killing shadows on the back wall; and typical, where I just used the overhead fluorescents in my office. Here the results were as you would expect: the cheaper the device, the worse it performed in low light. Specifically, the cheaper devices boosted the gain, which produced noticeable graininess in the image. Graininess is bad enough in itself; but since it adds motion to the video, it also exacerbates compression-related artifacts. All of this is tough to see in the static image presented in Figure 8 (below), but if you play back the videos, it’s very obvious.

Figure 8. Good lighting reduces noise and shadows on the face, producing a more even image. Click the image to see it at full size.

What you can see in Figure 8 is that the optimal dual-key lighting produces balanced, even lighting. In contrast, relying on overhead lighting will almost always produce shadows on the bottom half of the face, and uneven lighting over the rest of the face if the subject isn’t absolutely square between two banks of fluorescents. Looking at the image on the right now, I might dial down the intensity of the softboxes in back to reduce the glare over my left shoulder, but the talking head is much more impressive on the right.

While the Vixia and Panasonic performed better in low light, that just means they projected the shadowed face on the left with less noise. So in all cases, optimal lighting was better.

The Net/Net

Regarding the camera, if I’m shooting someone in a webinar, I’m bringing out the Panasonic. The image is subtly better and the extra hassle is worth it--so long as I’m behind the camera, not producing a selfie. For audio, I would hook up my wireless lavaliere system, and cycle that through the camera, capturing audio and video with the same capture device. Though Wirecast makes it simple to mix audio and video from different sources, this can cause slight synchronization issues.

If I’m producing a close-up webinar of myself, I’ll use the Logitech Broadcaster, or get a Windows-based, high-end webcam with a microphone input. A very cheap non-powered lavaliere can do a lot here to boost audio quality.

Whatever your selected device, optimal lighting is absolutely critical. The problem is, if you’re shooting close to a wall, like I was, it’s hard to light the subject without producing shadows on the wall, which I find distracting. So this means two lights on the back wall, two on the subject. Fortunately, softboxes are cheap; you can get 4 good lights for under $200. If you’re not shooting close to a wall, you probably can just use two lights, or even one light directly behind the camera or webcam, so long as the subject doesn’t get the deer-in-the-headlights look.