In this episode of the Photo Business Help Podcast, I’m going to talk photo history and the camera obscura and the science of how it works.
This stems from before folks invented cameras, before they were able to actually record the light impression that now goes onto our sensors or would normally go into film. They used something called the camera obscura. Artists use this they would they would tack up canvas on the wall on the other side of the camera obscura have an easy opportunity to outline and draw from the image being projected.
So what the heck am I talking about? A camera obscura is essentially a dark closed room, or a box, and this box has a tiny, tiny hole on one side of it.
The hole has to be small enough in proportion to the size of this box to make the camera obscura work properly. So basically it's just a giant box. It could be the size of a room. It could be variety of different sizes, but the key part–the whole thing–is that the little hole that the light is coming through needs to be the proper proportion to the actual box itself.
So what happens when this light comes to this little tiny hole? This is the part that I think is really cool because it's just pure science. And I think it's one of those phenomena that is just sort of amazing.
When the light comes through the little hole, it transforms and creates an image on the next surface that it meets, which would most likely be the wall. On the other side of the room, the image is automatically inverted or flipped upside down. Which is why most cameras have a mirror inside.
Now they're using mirrorless. But that's the main purpose of why cameras have a mirror inside of them.
According to the Wiki article, “rays of light travel in straight lines and change when they are reflected and partly absorbed by an object retaining information about the color and brightness of the surface of that object. Lit objects reflect rays of light in all directions. So small enough opening and a screen only lets through rays that travel directly from different points in the scene on the other side. And these rays form an image of that scene, when they're collected on a surface opposite from the opening.”
Essentially, it's a really cool science thing that we've managed to turn into the cameras that we know today. Thank you for checking out more photo history on the camera obscura and the science of how it works.