Camera ISO Explained as Fast as Possible

Getting the hang of your new DSLR involves a lot of work. There are a lot of buttons and dials, not to mention the menu, which can take a toll on you while you’re learning. There are a few  basics of photography and cameras that you need to master before those dials start to make sense. One of them is the ISO. Techquickie provides a quick initiation into the basics of ISO:

What is ISO?

ISO stands for International Standards Organization. That’s the geeky part—and we won’t go into that. ISO is a setting on your camera that is useful not only in low light situations but also when there is a lot of ambient light. In low light situations using each increasingly higher ISO number reduces the quantity of light that you need to make a proper exposure.

Remember the good old days of film? Photographers brought film for specific types of uses. These films had speeds marked on them: 100, 200, 400 and so on. ISO numbers are the same. When you move from ISO 100 to ISO 200, you cut the amount of light you need for a proper exposure by half.

ISO makes a lot of difference when you have to use a small aperture and there is not enough light to go around. Let’s say a group photo at the lobby or a swimmer at an indoor pool with poor lighting.

low light photography with high ISO

Higher ISO in low light is better than using on-camera flash

But the usefulness of ISO doesn’t end with low light photos only. Even in good lighting when you need to freeze action, cranking the ISO makes a lot of sense.

higher ISO in bright light

Higher ISO in bright light assists in using faster shutter speed

Does leaving your camera set on a high ISO make sense?

Going by the advantages, you might think just keeping your ISO on a high setting is a good idea. But in actuality, a higher ISO will always introduce noise into your images. The higher the ISO, the more noise. Modern digital cameras have excellent noise suppression properties. But even with that if you crank up the ISO too high noise will be evident.

selecting the right iso for your images

Leave ISO at a high setting when you need true colors and greater highlight and shadow details.

In even lighting situations low ISO produces realistic colors. So, that’s yet another important point to look out for. Overall, just like in the days of film, use a small ISO number for the most part. Crank it up only when you need to.

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One Comment

  1. Russell says:

    Great article – but do not perpetuate the myth that ISO is an the abbreviation for a non-existent ‘International Standards Organization.’ ISO is the trade name of the International Organization for Standardization (abbr to IOS), formed in 1947 who since that date have based their name, ISO, on the Greek word isos, which means equal.

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