Page 155 - PPL-engelsk 2025

Human Performance

They detect motion but not colors or details

Rods operate during both day and night and form the basis of peripheral vision.

Night vision is possible because multiple rods are connected to a single optic

nerve, increasing the surface area and allowing them to detect light with less

intensity.

2.5.1.4 Visual perception

Here is a small figure illustrating how the brain interprets inputs from central

vision.

Unconsciously, you throw away that one “one”.

Where are the lines thickest?

You may also know the illusion of two lines. One line ends

with arrows, and the other ends with reverse arrows.
Both lines are equal in length, yet they appear different.

Have you noticed the size of the sun just before it sets compared to when it is

higher in the sky?

It often looks larger near the horizon than higher in the sky.

Misperceptions occur in the brain's interpretation of visual impressions.

For example, we can be deceived about distances. On a clear day, for example,

you can see the pylons on the Little Belt Bridge from a long distance, but if you

guess how far away, they are, they are often much further than you initially

thought. The opposite is true in poor weather, as people tend to overestimate

distances.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 155