Shadow Ratio

The ratio of an object’s height to its shadow length. Multiply the height of any object by the shadow ratio to calculate the length of the object's shadow.

Sun

The star at the center of the Solar System. Learn more on Wikipedia.

Sunrise

The instant at which the upper edge of the sun appears on the horizon in the morning. In fact, sunrise occurs before the sun actually reaches the horizon because the sun's image is refracted by the Earth's atmosphere. Learn more on Wikipedia.

Sunset

The instant at which the upper edge of the sun disappears below the horizon in the evening. Sunset occurs after the upper edge of the sun reaches the horizon because the sun's image is refracted by the Earth's atmosphere. Learn more on Wikipedia.

Star Trail

When you take a picture of stars in the night sky with a long exposure using a camera on a fixed mount, there is a trail of stars. This line of light corresponds to the change of positions of the stars on the photographic medium caused by the rotation of the Earth during the period when the shutter of the camera is held open. Learn more on Wikipedia.

Shutter Speed or Exposure Time

The effective length of time a camera's shutter is open. Learn more on Wikipedia.

Subject Distance

The distance between the lens of a camera and a subject being photographed.

Shooting Interval (Time lapse)

Time between two consecutive shots or frames during the Event. A longer interval will result in a shorter, faster running video.