A shadow depends on more than the object
A shadow forms when an object blocks some light that would otherwise reach a surface. The same post can cast a long or short shadow without changing height. Light direction, object position and surface slope all matter. When comparing photographs, first ask whether these conditions are similar. A change in shadow size does not by itself demonstrate that the object moved or that an image was manipulated.
A lower Sun produces a longer shadow
On horizontal ground, a vertical object tends to cast a longer shadow when the Sun is low and a shorter one when it is high. Through the day, the Sun’s apparent movement accompanies Earth’s rotation. Shadow direction changes too. The exact pattern depends on location and season. It is incorrect to assume that the shortest shadow always occurs at twelve o’clock on a civil clock.
Compare without looking directly at the Sun
Choose a fixed object visible from a safe position and observe its shadow at two or three times. Record the time and keep your viewpoint consistent. Never look directly at the Sun or use optical instruments to observe it. Do not mark someone else’s property, and avoid roads or busy paths. Photograph the ground if useful, then compare the images while noting changes caused by clouds or other obstacles.
Recognise the limits of a shadow clock
A sequence of observations may reveal a relationship between light, direction and time. It does not automatically turn a post into a calibrated sundial. Orientation, latitude, season and the distinction between solar and civil time matter. Describe what you actually observed before assigning times to marks. The photograph in this article is illustrative; it is not a measurement or a record of the suggested activity.
