Twilight photography requires imagery to be captured after Sunset, during evening civil twilight, but before it is Night.
The issue is that Drones cannot be flown at ‘Night’ without special approval. (CASR 101.095)
Therefore, careful planning is required to make ensure we comply with legislation by taking off and landing before it is night. But what is meant by night?
1. WHAT IS ‘NIGHT’?
Night: That period of time between the end of evening civil twilight and the beginning of morning civil twilight. [Aeronautical Information Publication (AIP) GEN 2.7 Sunrise/Sunset Tables]
‘Night is defined, for aviation purposes, as the period of darkness from the end of evening civil twilight to the beginning of morning civil twilight’ [CAAP 5.13-2(0) Section 3.4.1]
2. WHAT IS TWILIGHT?
Diagram 1, shows the period between Sunset and Dusk Is ‘twilight’. This is the same as ‘civil twilight’.
Diagram 2, shows many versions of ‘twilight’ but we only care about WHEN ‘civil twilight ends. This diagrams shows that ‘civil twilight’ ends when the centre of sun disc is 6 degrees below horizon.
For a photography point of view, civil twilight is approximately the limit at which solar illumination is sufficient, under clear weather conditions, for terrestrial objects to be clearly distinguished. There is enough light from the sun during this period that artificial sources of light are not needed to carry on most outdoor activities