Last weekend I decided to shoot an urban landscape. I've seen some nice shots of the Washington skyline from across the Potomac and figured I might get something nice from the Marine Corps War Memorial or the Netherlands Carillon in Arlington. The weather forecast predicted clear skies. (That was no shock for me; clouds hate me.) So, in the absence of clouds, I thought I might get something interesting by shooting during twilight.

Dawn on Washington Morning twilight is the period beginning at dawn and ending at sunrise. (Wikipedia, Twilight (as of October 3, 2012).) There are three different defined periods of twilight, the distinctions between which are significant for photographers because the nature and quality of the light changes significantly between dawn and sunrise.

The periods in sequence are astronomical twilight, nautical twilight, and civil twilight. Astronomical twilight (when the center of the sun is between 12° and 18° below the horizon) is quite dark, as most stars are still visible when away from urban light pollution. With nautical twilight (when the center of the sun is between 6° and 12° below the horizon), general outlines of ground objects may be distinguishable, but otherwise difficult to see. With civil twilight (when the center of the sun is between 6° below the horizon and dawn), objects are clearly distinguishable, but the sun is not yet visible above the horizon. (Id.)

Daybreak on Washington I took the first photo precisely at civil dawn. The sky is a beautiful purple and the trees by the Potomac are mere outlines. Technically, I took the second photo five minutes after sunrise, but because buildings block the horizon, the effective sunrise in a city is a bit later. I shot the second photo just moments before the sun appeared. The sky is a beautiful orange color and detail is visible in the trees by the Potomac.

I'm pleased with the way my urban landscapes turned out, but I'm already planning to return for another try. I'd really like to get a sunrise with some clouds. I also want to try the landscapes with colder weather. Last weekend was relatively warm and very humid. The warm and humid air distorted the light and diminished the clarity of the images. I should be able to get something really good in late autumn or winter.