Civil, Nautical, and Astronomical Twilight
The three twilight phases describe how far the sun is below the horizon and how dark the sky has become.
Civil twilight
Civil twilight is the brightest phase. There is usually enough natural light for many outdoor activities, and it is often useful for photography without a fully black sky.
Many blue hour cityscape images happen around civil twilight.
Nautical and astronomical twilight
Nautical twilight is darker and can create a deeper blue sky. Astronomical twilight is darker still and leads toward full night.
For stars and deep night work, wait until astronomical twilight is ending or complete.
Frequently asked questions
Which twilight is best for city photos?
Civil and nautical twilight are usually best because the sky still has color.
Which twilight is best for stars?
Astronomical twilight or full night is better for stars.