ISO
The ISO is one of the 3 fundamentals every photographer should know about. If you do not know the two others feel free to read about them (aperture & shutter speed).
The ISO is the sensitivity of the camera sensor to light. This means that by adjusting it on your camera you will be able to make the sensor more sensitive to light or less sensitive to light. The camera sensor is the most important and also the most expensive part of your camera, it gathers light and transforms it into an image.
The camera settings are completely different from one to another, so the range of ISO will vary depending on your camera, all cameras have a base ISO it is the lowest ISO at which your camera can take a picture. There are also cameras which will let you shoot at much higher ISO than others.
There is low ISO such as 100, 125, 160... And high ISO such as 4000, 5000, 6400... It is very easy to understand how this concept works.
By understanding the previous concept, it is easier to understand how playing with ISO settings can affect a picture.
The ISO is the sensitivity of the camera sensor to light. This means that by adjusting it on your camera you will be able to make the sensor more sensitive to light or less sensitive to light. The camera sensor is the most important and also the most expensive part of your camera, it gathers light and transforms it into an image.
The camera settings are completely different from one to another, so the range of ISO will vary depending on your camera, all cameras have a base ISO it is the lowest ISO at which your camera can take a picture. There are also cameras which will let you shoot at much higher ISO than others.
There is low ISO such as 100, 125, 160... And high ISO such as 4000, 5000, 6400... It is very easy to understand how this concept works.
- When the ISO is low, then the sensitivity of the camera sensor to light is also low.
- When the ISO is high, then the sensitivity of the camera sensor to light is also high.
By understanding the previous concept, it is easier to understand how playing with ISO settings can affect a picture.
- If the environment where you are going to take a picture is very bright, then you should use a low ISO.
- If the environment where you are going to take a picture is dark, then you should crank up the ISO.
If you are taking 2 pictures in the same environment, with the same amount of natural light and by only changing the ISO you will be able to see that: by using a low ISO, the final picture will be darker than the same picture with an high ISO. That is because the sensor of your camera is less sensitive to light with a low ISO than with a high ISO.
Another important thing to know about the ISO is that when you are using a high ISO your final picture will have more grains or "noise" than a picture with a low ISO. Normally, people say that it is always better to use a low ISO to avoid noise. Yes, it is only true if you are using a too high ISO, because with a very high ISO, the quality of the picture can start to deteriorate. Otherwise, it all depends on you and what final picture you want.
Another important thing to know about the ISO is that when you are using a high ISO your final picture will have more grains or "noise" than a picture with a low ISO. Normally, people say that it is always better to use a low ISO to avoid noise. Yes, it is only true if you are using a too high ISO, because with a very high ISO, the quality of the picture can start to deteriorate. Otherwise, it all depends on you and what final picture you want.
In the picture above we can see that a higher ISO leads to a grainy picture.
Above we can see two different Canon cameras. As you can see the menu is different for every camera, even if it is different you will be able to change the ISO in manual mode for both cameras. Their base ISO is 100.
Above we can see that the Canon 60D and the Canon Rebel T1i have both the same base ISO (100), however, the 60D have a lot more ISO options than the T1i, It also have an higher maximum ISO.