Variation of shadow length under street lamp

The following is an explanation about the change of shadow length under street lamps:

The change of shadow length under street lamp is caused by the change of object height, street lamp height, distance between object and street lamp and observation angle. Below we will explain in detail the reasons for the change of shadow length.

First of all, when the height of the object is higher than the height of the street lamp, the shadow generated by the object under the street lamp is longer. This is because the light emitted by the street lamp forms a dark area under the object, and this dark area is the shape of the shadow. The length of the shadow mainly depends on the height of the object and the height of the street lamp, as well as the distance between the object and the street lamp.

Secondly, when the height of the object is lower than the height of the street lamp, the shadow generated by the object under the street lamp is shorter. At this time, the light emitted by the street lamp will shine from above the object, so there will be no obvious dark area under the object, and the length of the shadow will be shorter.

In addition, the change of observation angle will also affect the change of shadow length. If you look at the street lamp from the side, the shadow will be longer than the front. This is because the illumination angle on the side is low and it takes a long distance to form a shadow as long as the front.

Besides the above factors, the change of time will also affect the change of shadow length. At night, because the sun has set, street lamps have become the main lighting source, so the length of the shadow will be longer than during the day. During the day, due to the high position of the sun, the shadow length is relatively short.

To sum up, the change of shadow length under street lamp is caused by the change of object height, street lamp height, distance between object and street lamp and observation angle. In our daily life, we can adjust these factors according to our own needs to control the length of the shadow, so as to achieve a specific effect or purpose.

For example, when shooting a movie or TV series, the director can control the length of the shadow by adjusting the lighting, shooting angle and actor position, thus creating a specific atmosphere or effect.