Introduction

We know light is an essential element to make a photograph. But what exactly is light? Let’s take a closer look. It won’t take long before we talk cameras in the next chapter, but please bear with me on this one. At first it sounds easy but the more you think about it, the more there is to know about light.

So, what is light?

We know that light gets emitted from a source but we don’t know what light consists of. Yet.

Brace yourself as we dive into some technical aspects. Light is electromagnetic radiation within a certain frame of the electromagnetic spectrum. As humans, our eyes are capable of receive these waves inside the visible spectrum. We see these waves as red, green and blue (*RGB), depending on their wavelength. All other colours are a combination of these three colours. Red and green make yellow, green and blue make cyan,  blue and red make magenta. All three colours together make white. If there is none of them, it is black since there is no light at all.

So, waves, wavelengths and colours. Got it! Is that all? Not yet, but we’re almost there. There is one last thing to tell. Note: if you feel like the above is difficult to understand you can skip this part. It is not essential but I find it quite interesting as a little bit more information about how light works.

Ever wondered what a rainbow is? When the light from the sun hits our atmosphere, all waves form a bundle and have the same direction and contain all three colours (RGB!). When the light hits a raindrop, the bundle breaks apart and each wavelength scatters in a different direction. Since we now see separate wavelengths, we see different colours; we see a rainbow!

You might want to watch this video on YouTube, explaining how light is affected by a prism.