It’s difficult to follow an instructor – and mimic positions, fingering, and technique – if the student has difficulty seeing exactly what is being presented. Without proper lighting, the experience will frustrate students, and by extension, the teachers trying their best to teach them.
Backlighting will solve the majority of lighting issues in an online lesson. LED lamps are excellent tools to place behind the computer, illuminating everything in front of the camera. Avoid excessively warm lights low on the Kelvin scale, as they’re unlikely to add as much definition to what’s in the camera view.
If classes are being delivered during the daytime, consider placing the computer in front of a large window with a large amount of natural light. If you decide to choose this method, be sure to carefully consider your professional background.
If possible, consider more than one extra means of lighting to enhance your appearance on screen. Test your lighting with several different placements to get the best arrangement.