What is the ISO on a Camera? – What you really need to know!
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Most people today only use the “auto” mode of their camera. If your camera is any good, you can still achieve some pretty decent photographs in this mode. However, you will never really have much control over how your photos turn out. Having a good camera is one thing, knowing how to use it to its full potential is quite another. This is why the only way for you to take truly breathtaking photographs is by learning how to manually adjust your camera. You’ve clearly already begun this journey simply by asking the question – ‘What is the ISO on a camera?’ So come with me, lets talk ISO and how to live your best photographer life!
“Having a good camera is one thing, knowing how to use it to its full potential is quite another.”
There are three main adjustments to make in every camera. These are the ISO, shutter speed, and aperture. Today, we’re going to dive in and take an in-depth look at the first of these, the ISO.
So, what is the ISO on a Camera?
Back in the days of film cameras, ISO, or ASA as it was called that time, indicated how sensitive a film was to light. The higher the ASA, the more light that film could capture. This is why photographers would use low ASA when taking pictures of bright subjects, and high ASA when taking pictures of dark subjects.
Film cameras are long outdated though. Today, we have digital cameras. We don’t need film anymore because every digital camera has a sensor built within. It is this sensor that captures light and converts it into an image on your camera.
This is where ISO comes in. ISO controls how sensitive the sensor in your camera is. Unlike film, where you had to choose the right ASA for what you were shooting, you can easily change the ISO of your digital camera anytime! When you dial the ISO up, your camera sensor becomes a lot more sensitive to light. Dial it down, your camera becomes less sensitive to light.
But what Does ISO do on a Camera?
Now that we know how ISO works, what does adjusting your ISO do to your images? Since increasing your ISO increases the sensitivity of your sensor, bumping up your ISO will also increase the brightness of your image. This is why if your subject is dark, you should use high ISO, and if it’s bright, you should set your ISO low.
ISO is more than just a simple brightness adjustment though. Just like the other two elements of the exposure triangle, aperture and shutter speed, adjusting your ISO will not only affect the brightness of your image. Doing this will also affect the noise of your image.
What is ISO noise?
It’s not the sound your camera makes when you take a shot of course. Rather, it’s that grainy look you get in your images when you use high ISOs. Try setting your ISO as high as you can go and get a shot, you will see what a noisy picture looks like. Your image will be full of colorful grains all over the place.
Generally speaking, you want to keep your ISO as low as you can go. This will give you a very crisp and high-quality image. Grainy pictures are usually seen as low-quality. Whenever you are choosing your ISO, however, you need to be careful that you don’t underexpose your image. If you get too caught up that low ISO means better quality, this will be a problem that you will run into a lot.
So how much ISO can you use without getting an overly grainy picture? This is something that depends on the camera that you have. If you have an old camera, your ISO should always be relatively low. The newest cameras today, on the other hand, allow you to use really high ISOs without having to worry about noise! You can read instructions or play around with your camera’s ISO, you’ll get an idea of how much you can add without ruining your image.
“You want to keep your ISO as low as you can go. This will give you a very crisp and high-quality image.”
Noise and grain aren’t always bad things though. Some people deliberately add grain to their picture to achieve an artistic effect. But unless you know what you are going for, it’s best to keep your ISO low to get a crisp image.
What Does ISO Mean on a Camera?
You might have heard of the term ISO from somewhere else before. This shouldn’t be a surprise, because the word ISO is not strictly a photography term. ISO stands for International Organization for Standardization.
This organization works to standardize proprietary, industrial, and commercial measurements. This way, the world will have a much easier time communicating, sharing, and trading with one another. They are in charge of standardizing a lot of things. One of these is none other than the sensitivity ratings on your camera.
Without standardized sensitivity ratings, you’ll find that the world of photography will be really confusing. Each camera manufacturer will have their own system of rating their sensor sensitivity. Thanks to this organization though, your ISO will always be the same no matter what brand of camera you are using. You can always expect the same results when you use ISO 100 or ISO 10,000.
Is Raising ISO Just Like Brightening Your Photo on a Computer?
Since lower ISO means less noise, you might have this idea to drop your ISO to purposefully underexpose your shot, and then bring the brightness up in an editing program. Will this give you a bright and crisp photo? The answer is no. If you do this, you will find that your brightened image is going to be even noisier than if you had just bumped up the ISO a bit.
This is because noise doesn’t appear because you use high ISO, Noise comes out when a dark subject or image is brightened – either by increasing ISO or brightening the image in the computer. Getting a low ISO shot and brightening it in your computer won’t free you from grain, This is why you should try to get the ISO right on camera every time. This way, you won’t have to add brightness on your computer anymore. This will only put even more noise than a high ISO will.
Do you have any other ISO Advice?
Don’t be so afraid to get some noise on your photos. If you need to bump up your ISO, bump up your ISO. Unless there is an overwhelming amount of noise in your picture, most people aren’t going to notice anything anyway. You should know that other factors, such as exposure and clarity, are more important than crispness.
Play around with your ISO. Practice makes perfect anyway. Play around, use high ISO, use low ISO. See how well your camera does with noise and grain. The more you do this, the faster you will know which ISO settings to use in any situation.
And finally, learn the other elements of the exposure triangle. Knowing how ISO works is important for sure. But it is only one side of a perfect triangle. To take great photos, you need to learn the whole thing and how they work with each other. Now that you know all about ISO though, you’re off to a great start!