Estimation of angles and distances

If you consider the distance to your right eye in front of you, do not forget that certain conditions bring the objects closer together and that others move them away.

Conditions that bring objects closer together:
- look up or down
- strong illumination of the object
- look at a surface of water, snow, sand
- the weather is very clear
Conditions that move objects away:
- the weather is foggy
- the color of the object merges with the background
- great straight line with the object at the end (avenue, street ...)
- wavy terrain

How to estimate distances?

(image issue du site de l'AGSE)

Before you begin, you must first know what the thousandth is: the thousandth is a measure of angle (such as degree or grade); he has 6,400 thousandths for a turn of 360 ° (1 ° = 17 thousandths); in fact, the thousandth corresponds to a meter of 1000 meters.
Once the notion of thousandth is understood, to evaluate the distance that separates us from an object, it suffices to apply the "formula of the thousandth":

Examples:
- A house 10 meters high seeing itself at an angle of 5 thousandths: 10/5 = 2 km

How to estimate Angles?

(image issue du site de l'AGSE)

L’astuce est dans ta main: Cette technique d'estimation des angles ne demande aucun matériel, si ce n'est d'avoir sur soi une main. Il suffit de placer cette main devant soi, le bras étant tendu, de fermer un oeil et de viser l'objet sachant que les doigts et la largeur de la main font ces angles (exprimés en millièmes)
Extrait de: l’Astrolabe, ETN Orientation