The LED's Challenge to High Pressure Sodium (Response / Debunking / Topic Expansion)

Sources: https://docs.google.com/presentation/... Original video:    • The LED's Challenge to High Pressure Sodium   The goal of this video is to expand on a topic covered by Technology Connections in his videos on outdoor lighting. Not only will additional information be given to provide context to the points made by Technology Connections, but additional factors of roadway lighting will be examined. This video is information heavy and may not be the easiest to follow along with, but including any less information would leave important issues unaddressed. 0:00 Intro 0:50 HPS spectrum 2:30 Rod vs Cone cells 4:18 Visual adaptation 6:50 Nighttime lighting vs night vision 8:08 Lighting survey examination 9:27 Dirty lighting fixtures 10:58 Psychology of brightness perception 12:49 Visual performance 13:29 Mesopic vision research 14:21 Post illumination pupil response 15:32 Metrics of light efficiency 16:57 Visual adaptation for roadway lighting 21:43 Melatonin disruption 25:21 Melatonin and hormonal tumor growth 26:30 Melatonin and human health 28:04 Biological stress 29:19 TC comments on local LED transition 29:34 Old vs New sodium lighting 30:46 Luminaire dirt depreciation 31:30 Light pollution 37:29 Atmospheric scattering 38:32 Light fixture optical design 39:34 Light intensity 41:20 Glare 43:08 Technology Connections lighting summary 45:20 Scotopic to Photopic ratio 46:09 S/P Ratio and LED marketing debunked 49:40 Technology Connections conclusion 51:07 Aging of the human eye 51:45 Ecological impacts of light pollution 55:41 Visual performance summary 56:57 Biological impacts summary 57:35 Conclusion on light source selection