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When conducting collaborative research between multiple laboratories, the amount of time it takes to travel between the labs greatly reduces efficiency. However, image quality is a major problem with ordinary videoconference systems, and this forces researchers to hold face-to-face meetings.
The number of popular instructors is limited, and frequently those instructors cannot provide lectures at branch schools because of scheduling conflicts. Also, with ordinary videoconference systems, the image quality is so poor that it is difficult to make out the words written on the blackboard.