How do I decide between different ISO levels on a digital camera?

A digital camera is used to take videos or still photographs, and sometimes it even takes both of them. It is much more sophisticated than an old film camera. There are many kinds of digital cameras, but the most common remains the compact digital camera due to its small size, therefore one can take it anywhere.

Digital cameras have a particular setting known as ISO. This is considered to be one of the principal advantages of digital cameras. It measures the film speed, the same as in the film cameras used in the past. Film speed refers to the sensitivity of the camera’s image sensor to light. Since a compact digital camera is already very small, the image sensors of such cameras have a diagonal of about 6 mm.

There are many ISO levels on a digital camera and they are used in different situations. The range of ISO levels which are found in an average digital camera are 100, 200, 400 and 800, but other digital camera often have 64, 160, 640, 800 and 1600 as well. The highest ISO level in some more sophisticated digital cameras is as high as 3200.

An important to keep in mind about ISO is that low ISO levels indicate slow film speed, whilst high ISO level indicate fast film speed, and when the level of ISO rises, it may consequently result in grainy and not so clear photographs. A photo taken at an ISO level of 100 is therefore much better than one taken at ISO 1600, thus if one is taking a photograph, it is wiser to select the lowest ISO level possible, however, the higher levels also have their own functions.

ISO 100. The lowest ISO level is generally used when photographs are taken outside in the sun i.e. on a beach, thus where light is abundant. It helps the camera to take clear photographs of very good quality and these photographs can be enlarged very easily.

ISO 200. In case of cloudy weather or indoors, when the environment does not have so much light, it is advisable to set the camera on ISO 200. The noise may slightly increase, but it is not noticed very much.

ISO 400. This level is ideal for situations where the photograph is to be taken in dimmer light, such setting is also advisable to use when a fast-moving object needs to be captured on the photograph, the reason being that higher ISO settings increase the camera’s shutter speed in order to recompense for the lack of light in the scene, as well as to enable the camera to immobilize the object moving in front of it.

Another ability related to ISO that a few digital cameras have is the automatic (auto) setting. In case this setting is selected, the digital camera itself chooses an ISO from the levels between 100 and 400 according to the amount of light and the mode of the camera.

The knowledge of the camera’s different ISO levels is very important in digital photography because it gives the photographer more power and control in the manipulation of the camera.