What is ISO? Dhavalilama’s Photo Basics
When it comes to improving your photography skills, no matter how early on into your career you may be—one of the best things that you can do is to have a really strong understanding of photography basics. This includes understanding ISO. So what is ISO ?
If you aren’t already familiar with ISO, or are still trying to get a grasp on this concept, this guide will help you.
ISO is one of the three main pillars of photography that can transform the look of your images. The other two pillars are shutter speed and aperture. ISO, controls the brightness of your photos and if you are looking to capture the best and clearest images possible—you need to understand ISO.
What is ISO?
There are a lot of people who utilize ISO on a daily basis, who still don’t really know what it means. They may know what it does, but first you really need to understand what this term actually means.
In simple terms, ISOs is a setting on your camera that will help brighten or darken your photo. ISO is measured in numbers, and as you increase these ISO numbers, your photos will get brighter. However, brighter isn’t always better, which is what makes ISO so complex.
What is an ISO Image?
You know what ISO is, but how does it impact your photo?
Raising your ISO can also show a great deal of noise or grain. This is what can impact the clarity of your photos, which is why you need to be careful when playing with ISO, as that brightness can ultimately impact the look of your images.
Common ISO Values
Just having a definition of ISO isn’t enough to really grasp this photography feature. While most people play around with their ISO numbers to get a feel for what it will do to a picture, it is best to have an idea of what the numbers actually mean first to save you time when you take your photos.
While some cameras can be slightly different and every camera has a different range of ISO values (or speeds), the following is the most common set of ranges you will find on most cameras.
ISO 100 (low ISO and darker images)
ISO 6400 (very high ISO with grainy images)
How to Change ISO
Every camera is slightly different when it comes to changing ISO. With certain cameras, there may be a ISO wheel where you can change the ISO value, while most digital cameras have an on-screen setting. You can also look for the ISO button on your camera to manipulate your ISO value.
Of course, when in doubt, check your camera’s manual! But don’t worry, it won’t be hard!
What is Base ISO?
The lowest native ISO, which in the example above would be ISO 100, is known as your “base ISO.” This is an important setting, perhaps the most important one to pay attention to as it will give you the potential to create the highest image quality—by minimizing the visibility of noise as much as possible.
Most digital cameras today will have a bas ISO of 100, but some older models may have a base of ISO 200.
What is ISO and How Should I Use It?
This is the biggest question that people tend to have when it comes to ISO and their photography. There are different situations where different ISOs are going to be appropriate.
When to Use Low ISO
While it is true that you should always try to stick to the lowest ISO possible (such as ISO 100 or 200), this isn’t always possible, particularly when you don’t have much light to work with.
In these cases, you should first try to work around the dark environment you are shooting in and attempt to still shoot in a low ISO. You can do this by using something like a tripod and a longer shutter speed (which will in turn let in more light and keep your camera from moving or shaking).
While this is typically preferred, especially when you are trying to get as crystal clear of an image as possible—there are certain situations where a high ISO is not only necessary—but may also be preferred. After all, there are high ISOs around for a reason.
When to Use High ISO
The most common situation when you want to use a high ISO is when you are fighting against motion blur and you will need to decide whether you want to take a sharp photo at a high ISO or a blurry photo at a low ISO. Say you are shooting something moving very fast, such as an athlete in the middle of a game or a bird flying through air.
If you raise the ISO and set a fast shutter speed—you can freeze your subject in motion and capture a bright, sharp photo instead of one with motion blur.
The most important thing to remember in situations such as this, or any situation with ISO is that there is always a trade-off.
Reducing Noise With ISO
The best way to reduce noise with ISO, is to simply use a lower ISO setting. Of course, this means a trade-off with your lighting. If you want to both bring in light and reduce noise, then you can open up your aperture more to a wider setting, use a flash or use a tripod.
These are all ways to balance light so you can use a lower ISO and get rid of noise and grain in your photos to get a crisp and clear final image. Remember, there is a trade-off with all of these settings, so you will need to do some good old-fashioned trial and error.
While it is true that you can technically take photographs without a detailed understanding of ISO, learning about this feature can only help you create brighter, clearer, more professional and more beautiful photos. ISO is one of the basic cornerstones of digital photography and with a general understanding of this feature you can take your photos to the next level.