Taking some pictures at night? Sounds easier than it is but knowing about twilight — that fleeting time just after sunset or right before the dawn — will help you capture some terrific shots.
For astronomers, the true definition of sunrise and sunset is when the upper edge of the disk of the Sun is on the horizon and one has a clear and unobstructed view. Not likely to see this unless you believe the earth is flat and live near the edge, but here’s some more practical astronomy…
Twilight is the interval of time before sunrise and after sunset, when natural light provided by the earth’s upper atmosphere is reflected to the surface.
Civil twilight begins in the morning and ends in the evening when the center of the Sun is 6 degrees below the horizon. During this time, objects on the ground are clearly seen and the horizon is sharp. Under clear atmospheric condition, the brightest stars are visible. Get that camera on a tripod during this time!
| Waiting for the Cleveland Dawn |
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Color photography will be outstanding with fantastic hues and fine peaking saturation. Work quickly though since time is limited. You may only see civil twilight for about 30 to 45 minutes depending on location, before transitioning into nautical twilight.
Nautical twilight begins in the morning and ends in the evening when the center of the Sun is 12 degrees below the horizon. Ground objects, such as ships, may be discerned but fine details are not; similarly, the horizon is hazy and often misty.
Astronomical twilight begins in the morning and ends in the evening when the center of the Sun is 18 degrees below the horizon — generally an hour and a half sunrise or on the other hand, after sunset. This is the period when the sun is just barely contributing to the sky’s lighting. There is a very faint amount of light and this is when morning photographers often scout the area to prepare for the sunrise.
| Cleveland After Dark |
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Preparation is essential and the best, most creative photographers often use a journal to chronicle the exact times and f-stops used when capturing their favorite sun shots. Changes occur rapidly and you may see as much as four changes in f-stop over the period of just several minutes. Or…just put your camera on ‘program’ and let it do the calculation for you!
Practice and preparation will pay off and soon you will be composing images of brilliant sunsets and dazzling sunrises!
[Excerpted from Photography Insights, Volume 1, by Scott Ober, MD Copyright © 2010 ALL RIGHTS RESERVED]