Let’s face it:

When learning something new in life, there is always something that seems harder than it should, and ISO in photography is one of those things.

In this article, I will not only teach you what ISO is but how you can use it to get the best images you’ve ever taken.

 

Sound good?

 

Then let’s get started.

 

 

1. What is ISO in photography?

 

 

The first thing to understand about ISO is that it is the final component of exposure, the other two being aperture and shutter speed.

If you are feeling unsure about either of those, check out the links to read my awesome articles that cover each, in-depth.

Feel free to also check out my in-depth article on learning photography.  This article can help you make sense and put together all of these components of exposure to help you become a better photographer.

iso controls digital sensor sensitivity

The digital sensor on a digital camera.

ISO is the setting that controls the sensitivity of the digital sensor light.  As you adjust the ISO setting, the digital sensor becomes more or less sensitive to light, depending on how you adjust it.

 

When shooting with film, ISO is the sensitivity of film to light, and can not be adjusted.  For you to adjust the ISO on a film camera, you need to put in a new roll of film rated to the particular ISO you seek.

 

ISO can seem complicated, but it really is not.  Adjusting the ISO down, to a lower number drops the sensitivity of the digital sensor. When this happens, more light is required for the proper exposure of the image.

 

Changing the ISO to a higher number raises the sensitivity of the digital sensor.  When this is done, less light is required for the proper exposure of the image.

 

 

LOWER NUMBER = LOWER SENSITIVITY TO LIGHT    HIGHER NUMBER = HIGHER SENSITIVITY TO LIGHT

iso settings chart

 

Let me teach you how to adjust the ISO on your camera.  Watch the video to see just how to do it.

2. How to adjust your ISO.

 

 

Adjusting the ISO settings can be different from one camera to the next, but the process is similar. First, look on the outside of your camera for a button labeled ISO.

If you have one, hold it down and use the command dial to adjust your ISO settings.  If you do not have an ISO button, then you will need to change your ISO from within the menu.

 

iso-button-in-photography

ISO button locations on different cameras.

 

If you are on Canon, look at the top by the shutter release button for an ISO button.  If you don’t see one, look for a Q button on the back.  That will take you into a quick menu where you can change your ISO.

 

For Nikon, look on the top as well as the back for an ISO button.  If you don’t see one, look for a lowercase i button on the back of the camera.  That button will take you into the info menu where you can set the ISO.

 

 

 

ISO CONTROLS TWO THINGS:

1 – LIGHT

2 – DIGITAL NOISE

ISO CONTROLS LIGHT

3. ISO in photography controls light.

 

 

Because ISO controls the digital sensor’s sensitivity to light, we can brighten or darken an image simply by adjusting the ISO.  Take a look at the swinging monkeys in the image below.

If we keep the other components of exposure the same, we can brighten or darken an image simply by adjusting the ISO.

 

 

ISO in photography controls light

 

 

ISO settings below 400 are for shooting outdoors or in bright, sunny conditions.  Setting the ISO somewhere between 800-6400 will increase the sensitivity of the camera’s digital sensor to light, allowing you to shoot indoor or at night.

Let me show you the graphic that I showed earlier:

 

 

iso settings chart

 

 

Be aware, For sunny outdoor shooting, I usually shoot at ISO 400.  For evening and indoor photography, I set my ISO setting one or two steps down from the maximum ISO.

 

ISO in bright conditions.

 

 

When shooting in bright conditions, the ISO should be set to 400 or below.  This will make the digital sensor less sensitive to light, which is exactly what you want because there is so much light around!

These images were shot at a very low ISO (100iso).

 

kids at the beach shot with low ISO



young girl at the beach shot with low iso

ISO in dark conditions.

 

When shooting dark conditions, you will want to have your ISO higher to make the digital sensor more sensitive to light.

This will allow the sensor to capture all of the available light, which is needed because there is not that much available.

These images below were shot with a high ISO (3200iso).

 

 

young girl reading shot at high iso



young boy reading shot at high ISO

 

 

4. ISO in photography controls digital noise.

 

 

The drawback to ISO, is that as you raise it to cause the sensor to become more sensitive to light, you also make it more susceptible to electrical interference; –even interference created by the digital camera itself.

This electronic noise then becomes part of your images as colorful speckles of discoloration spread throughout the picture.

 

Let’s take a look at the monkeys again.  As the ISO increases so does the digital noise, and it begins to ruin the image.

 

 

image-showing-digital-noise-increase-as-ISO-increases

 

 

Through software, digital noise can, to some extent, be removed to repair the picture.  If the digital noise is too high, the image may be ruined.

To learn about Lightroom and fixing noise, check out my course, “Essential Skills for Photographers in Lightroom.”

 

digital noise from high ISO

This image shows digital noise caused by high ISO.



digital noise reduced with Lightroom.

This image shows how the digital noise caused by high ISO was fixed in Lightroom.

 

If you find that your images have too much digital noise in them, you will need to use a lower ISO setting to remove the noise from the pictures.

 

Newer cameras are much better at delivering clean images, free from digital noise –even at higher ISO settings.  If even at lower ISO settings you find the amount of digital noise unacceptable, it may be time to upgrade your digital camera.

5. Using Auto ISO in photography.

 

 

Auto ISO allows the camera to select the ISO setting based on available light and the current aperture and shutter speed settings.  Auto ISO takes selecting ISO out of your decision process.

I shoot in auto ISO and would recommend it to you as well.  There can be problems with auto ISO, especially on older cameras.

With older cameras, there is no way to put limits on the ISO selected, allowing the camera to pick too high an ISO and destroying some images with digital noise.

 

Newer digital cameras, however, allow you to set the maximum ISO that the camera can pick when in auto ISO mode.  These limits will keep the camera from choosing those very high ISO settings and ruining images with an abundance of digital noise.

 

If your camera doesn’t have the option to limit auto ISO, I would suggest not using it when shooting in dimly lit situations.

 

Setting Auto ISO on your camera.

 

To set auto ISO, you will need to do more than simply go into the ISO settings and change it to auto.

You will need to dive into the menus and find the ‘ISO sensitivity settings,’ and change it from there.  Let me teach you.

 



Setting auto ISO on a Nikon.

 

nikon menus for setting auto ISO

Menu’s on a Nikon to set Auto ISO.

ISO SENSITIVITY – This is the lowest ISO the camera will select when auto ISO is turned on.  Be careful, this is what you set when you change your ISO with the button on the camera body, and if you accidentally set it too high, the camera will never shoot at a lower ISO setting.  I would set this one stop above your lowest, generally at 200 ISO.

 

AUTO ISO SENSITIVITY CONTROL – This is how you turn auto ISO on and off.  Set this to ON.

 

MAXIMUM SENSITIVITY – This is the maximum ISO setting your camera can use with auto ISO.  I would recommend you choose one or two stops below the maximum ISO setting available in the camera menu.  If your camera allows up to 6400 ISO, set the ISO at 4000.

 

MINIMUM SHUTTER SPEED – Remember, when deciding the proper exposure for an image, there are three things are to be considered: aperture, shutter speed, and ISO.

When using auto ISO, and the camera determines there is not enough light for the proper exposure, it will try to add light by first lowering the shutter speed.  The camera does this to avoid digital noise.

Once the shutter speed drops to the number you set here, the ISO will begin to rise to add more light to the image.

 

Remember, if the shutter speed gets too slow, the images will be blurry.  To avoid blurry pictures, I would suggest setting this to 1/125 (or as close to it as you can get).

This setting tells the camera not to allow the shutter speed to drop below this number and instead begin raising the ISO to get enough light for the proper exposure.

 

Setting auto ISO on a Canon.

 

canon menus for setting auto ISO

Menu’s on a Canon to set Auto ISO.

ISO SPEED – This is how you turn auto ISO on and off.  Set this to AUTO.

 

ISO SPEED RANGE – Here you can set both the maximum ISO and the minimum ISO available when using auto ISO.  Remember to avoid the highest and lowest ISO settings.  For the minimum set an ISO speed of 200 and for the maximum set it one stop below the highest ISO setting available.  If your camera has a maximum ISO setting of 6400, set it one stop below, at 4000.

 

MINIMUM SHUTTER SPEED – Remember, when deciding the proper exposure for an image, there are three things are to be considered: aperture, shutter speed, and ISO.

When using auto ISO, and the camera determines there is not enough light for the proper exposure, it will try to add light by first lowering the shutter speed.  The camera does this to avoid digital noise.

Once the shutter speed drops to the number you set here, the ISO will begin to rise to add more light to the image.

 

Remember, if the shutter speed gets too slow, the images will be blurry.  To avoid blurry pictures, I would suggest setting this to 1/125 (or as close to it as you can get).

This setting tells the camera not to allow the shutter speed to drop below this number and instead begin raising the ISO to get enough light for the proper exposure.

6. Conclusion.

 

ISO is a powerful tool in photography that allows you to capture the image you want in any light.  The major frustration of having blurry images when shooting indoors is almost entirely removed by simply knowing and adjusting your ISO.

As with anything, I can teach you but the real help comes as you go out and practice.  So get out there, and practice adjusting the ISO in your images.

learn essential camera skills

The super-awesome free course on lighting.

Bride2

Ready to learn about lighting?

Whether shooting indoors our out, my free online course on lighting is for you. Simply hit 'sign me up' below and enter your first name and email address.

Take your lighting skills to the next level!

Unsubscribe at anytime with no hard feelings.

Learn how to get awesome light anywhere!

 

Great photography begins with great light, so it's imperative that as a photographer you learn how to find and capture great light.

My FREE online course is self-paced, so learn at your own pace and schedule.

Sign up now to get started, and learn how to get great light no matter where you're shooting.

Woohoo! Now check your email to finish signing up.

Hero Starter Pack Presets

Enter your name and email so I know where to send the FREE presets!

Success! Check your inbox for the presets.

Pin It on Pinterest

Share This