by Dave Morrison, Senior Product Manager and William Franco, Director of Video Engineering
Why are cameras so important? Since their inception they have changed our image of the world, either capturing moments forever or transporting live visual images instantaneously across time and distance.
Since the early beginning, camera technology has improved vastly. Today, they provide the highest quality in the smallest packages that are very affordable, resulting in everyone having one in their pocket, computer, phone or vehicle.
When looking for a new camera there are several parameters used to qualify the right one. It’s important to note though that all new consumer cameras are digital. This has been the single biggest impact on cameras in over 100 years. Other important purchasing considerations include: ease of use (i.e. point/shoot), image quality (number of pixels), zoom lens (i.e. 4x optical versus 2x digital), LCD monitor (i.e. 2 versus 4 inches), full motion video, battery life, and the overall size of the camera.
In the video conferencing market, cameras have evolved just as much as their counterparts in the consumer market. So what are these changes and how have they impacted the video communications market?
Excluding the major impact the Internet had on accessibility and reliability of video conferencing, the next largest impact is the image quality improvements through the introduction of high definition video. Driven by the HD broadcast and HD display industries, HD video conferencing now provides full 1080p resolution providing users the clearest images and face to face clarity.
Combined with high definition resolution there are two factors that significantly improve image quality. First is motion handling. When viewing video, whether live or recorded, an image that is broken or jittery it can be very distracting. Therefore, maintaining a constant frame rate regardless of bandwidth is critical. Frame rate is measured by frames per second (fps). Today’s video conferencing systems can support 30 fps and 60 fps thus providing lifelike image quality for its participants. Second, high definition also introduced a wider viewing screen or aspect ratio, in its 16/9 format versus the previous 4/3 format. This wider viewing screen, combined with the high quality image, has changed how video conferencing cameras are used in meeting environments. Previously, users would continuously pan the room to find and zoom in on the speaker. High definition video cameras can be positioned once to capture entire rooms and/or participants. This impact reduces distracting camera movement and allows all participants to focus on what is important – their meeting!
There are several technical aspects to consider when choosing the right video conferencing camera. Support for the highest possible resolution (1080p) and frame rate (60 fps) is important as well as the number of pixels which in turn support sharper image quality. The camera optics is critical in allowing light transmittance through the kens barrel to the image sensor resulting in better low light handling, which in turn increases the signal to noise ratio (SNR) resulting in better image quality. The optics also impacts the amount glare (light reflecting on the lens and resulting ghosting image quality) and distortion (the bowing of straight lines).
Other aspects to consider are zoom capabilities and whether this is optical zoom versus digital zoom. The former allows users to focus on the subject with no loss on video quality whereas the latter allows the same focus yet does so by discarding pixels and scaling up the remaining pixels which softens the image.
Other considerations within the overall video conferencing solution are the number of camera presets and the supported cable lengths between the video codec and the camera.
Similar to the digital cameras in the consumer market, video conferencing cameras continue to evolve and improve.