¡Hablemos de fotografía! - El Diafragma. // Let's talk about photography! - The Diaphragm. (ESP-ENG)
Hello friends, good vibes everyone.
As we said in the previous post in photography there is something called the "holy trinity" or in a less mystical way the "exposure triangle" which is made up of the ISO, the diaphragm and the shutter speed. As we already talked about the ISO, today it is the turn of the diaphragm and in everything that helps in this photographic world.
- Vamos a comenzar definiendo que es el Diafragma.
We are going to start by defining what the Diaphragm is.
The diaphragm is a tiny device found in our lenses which allows light to pass through to the sensor of our cameras. This is done thanks to small "windows" that open or close, allowing more or less light to pass through, as we require. In less complicated terms it would be like the iris in our eyes.
As you can see in the photo that I published in the professional cameras the diaphragm is represented in two ways, one graphic and the other numerical. The graph is the one that shows us how open the diaphragm is and the other is the one shown in f / stop which is nothing more than the diameter of said aperture.
In this first example we see that the aperture is at f3.5, that is, a fully open diaphragm so it will let a large amount of light pass through. This value is ideal for dimly lit locations. The lower the value, the more light it lets through.
In this second example I show you the opposite case of the previous one, a totally closed diaphragm represented with an f22 and a graph that shows a minimum opening. This is the case where there is an excess of light and we have to close this device so that the least possible amount of illumination passes through. So, the higher the numerical value, the less light will pass through.
But there is also something that depends a lot on the diaphragm which is nothing other than the depth of field. At a lower number than this value the depth of field will be minimal since only a very small part of the object is in focus. On the contrary, when we have a fully closed diaphragm this depth of field will be wider, the whole object will appear in focus.
This also depends on the focal length and especially on the size of the sensor. There are lenses that are f1.4 where the depth of field is incredibly small, making it ideal for portraits since the person will be in focus with the entire background out of focus, giving off the bokeh effect. Subject that we will talk about in the future.