Night flying has a higher accident rate than identical day flying, both in UAV and manned aviation. Why? Depth perception is severely distorted, as is reaction time. There are also visual illusions that need to be recognized and mitigated. Learn how to fly your UAV / sUAS at night - LEGALLY, SAFELY and EFFECTIVELY! This manual is designed for UAV pilots to understand night flight theory: how to prepare your aircraft and flight techniques for night flight, how to acclimate your eyes, how to avoid light contamination when lighting subjects, and most importantly, how to properly assess and plan for the risks associated with night flight (as waived per Part 107.29). To best understand the difference between day sight and night sight, this manual goes into great detail on the physiological shifts as a UAV pilot moves from day flights into night flights, detailing how eyes work at night and why visual illusions (such as autokinesis and night landing illusions) occur. This manual is a summary of industry best practices for UAS night flying.