Eye contact & Pepper’s Ghost

A/V consulting is about planning systems to solve problems relating to visual and aural communications.  Putting displays where you can see them is part of this.  And for as long as we’ve been doing distance education, the reverse is also true; we need to put cameras where they can see us.

The question is straightforward.  The instructor and students need eye contact to stay engaged, and for distant students, this means the instructor looking at a student (where is the monitor?), and the student looking straight back at the instructor (where is the camera?)  The solution in a lecture hall has long been a confidence monitor at the rear wall, or lectern, or maybe first row of seats, and a camera nearby.  In a seminar room, we know we’d like to put a camera in the middle of the front wall, but we have a markerboard there, or a video display, and so put the camera above, below, or one side.  The best solution can be much debated, and in our office is the subject of many conversations at the coffee pot.

Which is where magic comes in.  More than 400 years ago, a technique was developed for combining two images for an observer in a fixed location.  Known as Pepper’s Ghost, the illusion involves a darkened room and half-silvered mirror, and is used today in amusement parks and elsewhere.  For fun reading, https://www.twowaymirrors.com/peppers-ghost-illusion/  But it’s real, and with practical applications.  In television production, we call this a teleprompter. 

All this is brought to mind as we optimize our designs for remote teaching.  Eye contact with students is essential, and has to be maintained as our students move online.  And their numbers are climbing; we now need to manage dozens of remote students, and read their names, and keep them engaged.  Where viewing distances are short (an instructor teaching from home), the teleprompter offers a good solution, a large display with centered camera.  In the classroom, where greater distance permits some camera offset, we now have a wall of monitors, each with a gallery of students, and each with its own camera. 

We’re asking technology to fill in for the absence of in-person conversation.  It can’t always do a good job.  But awareness of simple things like camera placement can go a long way, and it needn’t carry a large price tag.