Blue hour is the period of twilight before sunrise and after sunset when the sky takes on a deep, saturated blue tone. Unlike the warm golden hues of golden hour, blue hour produces a cool, serene light that creates a distinctly atmospheric mood in photographs. It typically lasts 20 to 40 minutes, depending on your latitude and the time of year.
What Creates the Blue Light
During blue hour, the sun is below the horizon but still illuminating the upper atmosphere. Shorter blue wavelengths of sunlight scatter more efficiently through the atmosphere at this angle, bathing the sky in blue while the indirect illumination keeps the landscape dimly lit. The result is a natural blue color cast across the entire scene that is difficult to replicate at any other time of day.
Camera Settings for Blue Hour
Light levels during blue hour are low, making a tripod essential for sharp images. Use your lowest ISO for maximum quality and set a moderate aperture (f/8 to f/11) for good sharpness across the frame. Shutter speeds will be long, often several seconds or more, which can create beautiful effects like smooth water and streaking clouds. A remote shutter release or your camera’s self-timer prevents camera shake from pressing the button.
Best Subjects for Blue Hour
Cityscapes are the classic blue hour subject. The deep blue sky provides a rich backdrop, and the warm artificial lights of buildings, streets, and bridges create a striking warm-cool contrast that is visually compelling. This balance between ambient sky light and artificial illumination only exists during blue hour. Before it, artificial lights are invisible against the bright sky. After it, the sky goes black and the contrast is lost.
Landscapes, seascapes, and architecture also benefit from blue hour light. Calm water reflects the blue sky beautifully, snow takes on ethereal blue tones, and buildings gain a dramatic, cinematic quality. Even subjects that photograph well in other light, like harbors, bridges, and monuments, often look their most impressive during this brief window.
Planning for Blue Hour
Blue hour is short and predictable. Smartphone apps and websites that calculate sunrise, sunset, and twilight times for your location let you plan precisely. Arrive early, scout your composition during the brighter golden hour period, and be ready to shoot as the light transitions. The most dramatic moments often last only five to ten minutes. Having your camera set up and your composition chosen in advance means you can focus entirely on capturing the light at its peak.
This guide is part of our comprehensive Landscape Photography resource.