What is ISO in Camera?

What is ISO in Camera? ISO is the most crucial setting in digital cameras. Professional photographers always depend on this setting. But not only ISO, good photography mostly depends on the three basic settings of the camera. They are Aperture, Shutter speed, and the ISO.

What is ISO in a Camera?

There is an organization which is also known as ISO, the International Organization for Standardization. But ISO Camera is not an organization. It is a setting in a digital camera for brightening or darkening the photos. ISO is a specific value that measures the sensitivity of the camera sensor to the light.

If anyone increases the ISO number in the camera, the photos will grow brighter. So, ISO can help you take amazing shots in darker areas. With the other two settings, such as aperture and shutter speed, ISO can be more effective.

However, using the ISO without knowing about it has serious consequences. Too much ISO also creates too much noise or grain. With a high noise, a photograph would not be a good photograph. Use ISO camera where it is needed, such as if you are unable to brighten the photo with the other settings.

Camera ISO Settings

ISO Camera Measurement

ISO also used in the traditional cameras that we know as film photography. In the old days, you have probably seen the film canisters. The film canisters were containing different numbers such as 100, 200, 400, 800, etc.

These numbers were the ISO for the cameras at that time. The higher the film number, the higher the sensitivity of the film.

Traditional Film

ISO Camera in Digital Photography

In digital photography, the ISO camera number can be up to 6400. and ISO 100 is the lowest. Now every digital camera sensor carries a different range of ISO values such as ISO 100, ISO 200, ISO 1600, etc.

The high value of ISO means the camera sensor is more sensitive to light. Using a high-value ISO camera, you can capture a brighter image in dark surroundings. But it will include more grain in the photo. As digital cameras are improving day by day, the photographer won’t face this problem soon.

Even now, you can buy a new model camera to use higher ISO in the dark for better images. With a faster shutter speed, you can use high ISO to capture a moving subject in the night which would not be blurry too.

Digital Camera Sensor

ISO Camera settings and grain

Most people keep their digital camera’s ISO to Auto mode. In auto mode, the camera selects the proper ISO according to the surroundings. But in most digital cameras, you can choose a different ISO.

If you set your camera ISO at a higher level, you will see more grain in the photos. Let’s see two pictures that captured with different ISO camera.

Comparing ISO

Here you see two images. The photo on the left side was taken at ISO 100, and the other one at ISO 6400. What is the difference between these photos? The photo on the right side is full of noise and grain as it was taken with a higher ISO. But the image on the left side looks cleaner because of the low ISO which is standard on most cameras. So, the photo with 100 ISO looks more lovely. When aperture and shutter speed is not enough to brighten your images, then you may need to increase ISO.

Which Points Should You Consider When Choosing ISO?

Here are the four essential things that you should consider when changing the ISO camera.


If there is enough light and you are trying to shoot the image with no grain, then using a low ISO would be a good idea. Your camera aperture and shutter speed are enough to lit the subject in a natural area.

Learn more about lighting in photography from our latest article about portrait lighting.


When you need a sharp image with some grain, then you can increase the ISO according to the light adjustment. The more you increase the ISO the photo will be grainier. And grain makes the image noisy. So with a standard ISO, you can have a little blurry and lovely shot of your subject.


Are you using a tripod when shooting? If you are using one and your subject is stationary with plenty of light, then a lower ISO would be best for the job. But if it’s dark and you don’t have a tripod then consider increasing the ISO.

Moving Subject

Using faster shutter speed for a moving subject is very hard. It is also tough to adjust the perfect aperture. So if you don’t have a tripod and your subject is moving, then you may need to increase the ISO.

moving subject

When You Need a Higher ISO?

The standard ISO in the digital camera is enough to shoot most of the time. Sometimes, you have to fight against motion blur, and you need to shoot a sharp photo at a high ISO. So, there are some situations you can’t ignore. Let’s see in which conditions you need a higher ISO to expose the shot correctly.


Everyone moves in a concert, and the low light can be a problem for shooting with the standard ISO camera. Besides, you may see the “no flash zone” at the concert. So, you have to increase your ISO to have a bright picture at a concert.

Birthday Parties

Usually, the room for a birthday party is dark and lighten up with many candles. So, you will have a nice moody short at a birthday party. But if you use flash for shooting, you may have ruined the mood of the room. It’s the moment you use a high ISO for shooting a perfect scene in the dark.

Indoor Sports Events

Every light source is artificial in an indoor sports event. You will never found a natural light source, and possibly your subjects are always moving. So, there is no way to use a higher ISO to capture moving subjects in the low lights.

Churches & Art Galleries

Using a flash is forbidden almost in every church, and the interiors aren’t lit well. Besides, Art Galleries are a moody place where you can’t use a flash. But churches and art galleries have shallow light inside. These are the place where you should increase the ISO in the camera.


ISO camera is an essential adjustment for digital photography. You can gain more control over your camera by using the proper ISO techniques. But before you have to understand when to use and when not. Just remember if you want a bright photo with the grain then consider using a higher ISO. Changing the ISO also depends on the shutter speed and aperture. So, if you have enough light using a longer shutter speed and aperture, then you don’t have to use high ISO.

If you are planning to buy a good camera, then read our guide about the best camera for photography. Here are some more photography tips you can read. Please read our guide about wedding photography, night photography, long exposure photography. By following these guides, you can excel in your photography skill. Please share with us if you have any queries about ISO camera.

Which is a perfect ISO for outdoor photography?

ISO 100-400 is the best range for outdoor photography. It can be increased if you need a faster shutter speed.

What is shutter speed?

The shutter speed used to define how long a photo can be exposed to light. It can be milliseconds or even minutes. Shutter speed is one of the three major elements of the camera.