Collaborative spaces are rapidly gaining momentum in higher education. With that said, didactic pedagogies aren’t going away any time soon. If nothing else, the classroom of the future needs a space to record presentations for students to stream later as part of a flipped classroom approach!
In collaborative classrooms, one factor that often requires less consideration is lighting. You frequently don’t have a dedicated “presenter location” to highlight. What’s more, you’re typically using traditional flat panel displays, rather than projection because students are in small groups and can be closer to individual displays. In some cases there may be a main display for everyone to view at some points, but in many cases, ceiling height prohibits a single screen of sufficient size to be seen from every seat.
With these concepts in mind, this article will cover a subject that is possibly the only technology aspect of presentation spaces that requires more design consideration than in collaborative spaces – Higher Education Auditorium Lighting.
The whole challenge of lighting a higher education presentation space comes down to a tradeoff between providing sufficient light for note taking, versus projecting a high quality image. Why is this only an issue in presentation spaces?
Presentation spaces are typically large and allow every student to focus on an instructor and one or more screens at the front of the room.
Every student in the room needs to be able to view these displays, so they need to be large (to be visible to those in the back of the room).
The most cost effective way to achieve those large images is still by using projectors and screen
Projection is very sensitive to ambient light. The brighter the room lighting, the more washed out the image appears.
The reason the image appears washed out is because the room lighting limits the darkest black that can be represented on the screen (projectors can only add light to the screen; they can’t take it away)
The quality of the image (either vibrant or washed out) is measured by what we refer to as contrast ratio.
This is different than the contrast ratio you see cited on projectors which is typically useless manufacturer marketing BS.
With these concepts in mind, let’s look at the 5 keys to proper lighting for higher education presentation spaces:
Provide a minimum of 3 lighting zones
The image at the top of this post is taken from the InfoComm AV/IT Infrastructure Guidelines for Higher Education document, an excellent basic reference on education space design. While this document doesn’t get into the specifics of technology or space design (it covers everything you can fit into 143 pages), it does an excellent job of covering all of the questions that you should ask during the design process.
What the image is depicting is the minimum lighting zone requirements for a presentation space (3 zones). Circuit 1 provides audience lighting (for note taking). Circuit 2 provides board lighting. The board lighting allows bright lighting for a whiteboard/chalkboard (when can we get rid of those chalkboards, please?) or low/off lighting levels when using projection. The presenter lighting (Circuit 3) may include task lighting and or key lighting (to highlight and provide focus on the presenter).
Provide lighting presets for different Minimum Contrast Ratios
Going back to our earlier discussion, the challenge in presentation spaces is to strike a compromise between having enough lighting for note taking, without washing out the projection screen (which reduces the contrast ratio). Some of the lighting for students in the front of the room will inevitably bleed onto the projection screen.
The solution is to provide multiple lighting presets that provide varying compromises for different circumstances. Per ANSI/INFOCOMM 3M-2011, this means creating presets with minimum contrast ratios of 7:1, 15:1, or 50:1 to serve Passive Viewing, Basic Decision Making, and Analytical Decision Making, respectively. This is just a fancy way of saying that we need presets for different compromises between image quality and lighting levels for note taking.
This is accomplished by taking measurements from several points in the room with a specific test pattern. I’m simplifying here. The full procedure is outlined in a 27 page document. In any case, audience lighting levels are then raised, storing as a preset at each of the levels noted above. As the audience lighting levels increase, the ability to take notes improves, while the video image degrades. Providing these set points at standard levels not only serves specific purposes, but can help retain consistency across a campus.
Control any exterior ambient lighting
While we are all becoming aware of the benefits of daylight on health and well-being, it does very bad things for the health and well-being of a projected image. We just can’t economically produce enough light to get a usable contrast ratio.
The traditional solution is to use the control system in the rooms to automate mechanical shades or blinds. Traditionally, this is programmed to happen whenever the projector is turned on in the classroom. With more sophisticated programming, it is possible to trigger settings, based on an ambient light sensor in the room.
If Ambient Lighting Cannot be Controlled, Use other Display Technologies
In most cases, the only other alternative has been expensive LED walls, or narrow bezel video walls. There are a lot of considerations here, in terms of cost, weight, heat, etc. There is one additional option that you may not have seen previously. A Danish company named DNP builds a screen technology that is unlike any other on the market. Instead of using a traditional high gain screen (which reduces viewing angle and reduces consistency), the utilize a lenticular Fresnel technology.
The full explanation is beyond the scope of this article, but the gist is that you can achieve very high contrast WITH high ambient lighting. Here is a link to a demonstration showing the difference between this technology and a traditional screen. This has not been possible previously. Due to their manufacturing methods, the screens are particularly cost effective in sizes below 120” diagonal.
Use Occupancy Sensing
Almost all of the manufacturers who build the control systems popular in higher education can also support Occupancy Sensors to shut off lighting (and just about anything else), when the room is not in use. Aside from the obvious savings on the light bill, this also allows for analytics on room usage, when connected to a central Secure remote management and monitoring (SRMM) system.
Following these few tips should help you create a learning environment with the best possible blend of image quality, lighting for note taking, and budget. These variables are the three points of a triangle that must be balanced in every presentation space. Proper zoning and the creation of multiple presets for specific applications is almost always the best compromise between these three competing objectives.
For more great articles, just like this one, be sure to sign up for our blog notifications. If you’d prefer to read about the other side of the coin, below are links to the first four parts of our series on collaboration spaces. These articles are not dedicated solely to education. We’re saving that topic for an upcoming series, so you’ll need to sign up for the blog to get the heads up when the collaborative education spaces series is published.