Welcome to my post ‘ Camera ISO Settings Explained ‘. The term ISO in photography has been around since the early days of film. It stands for Industry Standards Organization. This is the governing body that sets the standards for sensitivity to light for photographic mediums such as film or a digital sensor. ISO also sets standards for hundreds of other products.
Sensitivity to Light
When we depress the camera button to take a photograph, light travels through the lens and is projected onto an image sensor that is placed inside the camera body. By the way, film used be where the image sensor is in modern digital cameras. The image sensor can be adjusted so it would react differently to light. It can be set to react fast or slow to the light falling onto its surface.
If you are shooting outdoors in a sunshine, you may want to set it react slow. Because there is an abundance of light available. You may run into the risk of making your photograph overly bright if you set it to react fast where more of light available. These settings are excellent choice for sharp images.
Indoor photography or where there’s lack of good light source, you may want to set the sensitivity to fast. These setting gives you a good starting point. Keep in mind higher settings can produce more grain and could rob your photograph from the finer details you may want in your photo.
The ISO is also referred to as the film speed. Of course the film is almost obsolete, so we will be talking about the image sensor. The speed is expressed as numbers. Typically, these numbers look like,50, 100, 200, 400, 800, 1600 and so forth. Notice how they double in size. Every time the ISO is increased or doubled, the camera needs half as much light to produce the image. My camera goes all the way up to 12800.
Smaller numbers reflect that the image sensor will react slow to light. Numbers in the range of 100 – 400 are useful for sunny beach days or sunny snowy days. Using these setting will give a desired exposure in bright situations.
Settings in higher ranges such as 400-800 are useful for indoors where standard household lighting is available. A flash unit may be required to fill in that extra needed light. As I have mentioned earlier, when we start going higher, the grain or noise in your photo could become a problem. Modern digital cameras are becoming more technically advanced. Engineers are constantly working to reduce noise yet still use a higher ISO.
Digital cameras can be set to auto ISO. This means the camera will automatically select the ISO based on the lighting conditions. Most point and shoot cameras, and cameras in you mobile phone are all automatic. The problem with auto ISO is that the camera raises the ISO if there’s lack of light, therefore producing images that are noisy. This is where learning a fully manual camera pays off. This allows you to control every aspect of the shot.
How to Select Best ISO settings
Photograph is a combination of ISO, aperture, and shutter speed. All three are dependent on each other. As guideline, use lower speeds in bright situations, higher speeds in low light or dim situations. In order to select the best ISO settings, you must also select the best aperture, and best shutter speed. This is called the Exposure Triangle. I will be writing a separate post on that topic. Also, learning by doing is the best approach. It is much cheaper nowadays to practice on a digital SLR camera, than it was on old film cameras.
I hope you have gained some insight on what is iso and how it is applied. Remember to read my other posts on “Lens Aperture Explained,” and “Shutter Speed Explained.” Please feel free to leave questions or comments below